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Copyright of Contemporary Accounting Research is the property of Canadian Academic Accounting Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Contemporary Accounting Research is the property of Canadian Academic Accounting Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we developed a theoretical model for the photothermal deflection technique in order to investigate the electronic parameters of three-layer semiconductor structures. This model is based on the resolution of thermal and photogenerated carrier diffusion-wave equations in different media. Theoretical results show that the amplitude and phase of the photothermal deflection signal is very sensitive to the nonradiative recombination parameters. The theoretical model is applied to one layer of InAs quantum dots (QDs) inserted in GaAs matrix InAs/GaAs QDs in order to investigate the QD density effects on nonradiative recombination parameters in InAs through fitting the theoretical photothermal beam deflection signal to the experimental data. It was found that the minority carrier lifetime and the electronic diffusivity decrease as functions of increasing InAs QD density. This result is also related to the decrease in the mobility from 21.58 to 4.17 (±12.9%) cm2/V s and the minority carrier diffusion length from 0.62 (±5.8%) to 0.14 (±10%) μm, respectively. Furthermore, both interface recombination velocities S 2 / 3 of GaAs/InAs (QDs) and S 1 / 2 of InAs (QDs)/GaAs increase from 477.7 (±6.2%) to 806.5 (±4%) cm/s and from 75 (±7.8%) to 148.1 (±5.5%) cm/s, respectively. [ABSTRACT FROM AUTHOR]

Scanning spreading resistance microscopy (SSRM) measurements were performed on GaAs thick films grown by hydride vapor phase epitaxy technology under different growth conditions to evaluate their carrier concentrations. For this purpose, a calibration curve was established based on a multilayer staircase structure grown by molecular beam epitaxy. The dopant calibration range measured by secondary ion mass spectrometry is from 5 × 1016 to 1019 cm−3. An abnormal phenomenon in the calibration process was explained by taking into account the parasitic parallel resistance of the calibration samples. Finally, the calibration curve was used to quantitatively analyze the carriers inside the Zn doping p-type GaAs film from 4 × 1016 to 1018 cm−3 range. We demonstrate here the applicability of SSRM to the in-depth analysis of thick epilayers, providing new inputs for the control of thick film technologies. [ABSTRACT FROM AUTHOR]

Strain engineering using ion beams is a current topic of research interest in semiconductor materials. Synchrotron-based high-resolution x-ray diffraction has been utilized for strain-depth analysis in GaAs irradiated with 300 keV Ar and 4H-SiC and GaAs irradiated with 100 MeV Ag ions. The direct displacement-related defect formation, anticipated from the elastic energy loss of Ar ions, can well explain the irradiation-induced strain depth profiles. The maximum strain in GaAs is evaluated to be 0.88% after Ar irradiation. The unique energy loss depth profile of 100 MeV Ag (swift heavy ions; SHIs) and resistance of pristine 4H-SiC and GaAs to form amorphous/highly disordered ion tracks by ionization energy loss of monatomic ions allow us to examine strain buildup due to the concentrated displacement damage by the elastic energy loss near the end of ion range (∼ 12 μ m). Interestingly, for the case of SHIs, the strain-depth evolution requires consideration of recovery by ionization energy loss component in addition to the elastic displacement damage. For GaAs, strain builds up throughout the ion range, and the maximum strain increases and then saturates at 0.37% above an ion fluence of 3 × 10 13 Ag/cm 2. For 4H-SiC, the maximum strain reaches 4.6% and then starts to recover for fluences above 1 × 10 13 Ag/cm 2. Finally, the contribution of irradiation defects and the purely mechanical contribution to the total strain have been considered to understand the response of different compounds to ion irradiation. [ABSTRACT FROM AUTHOR]

Non-contact photothermal pump-probe methodologies such as Frequency-Domain Thermo-Reflectance (FDTR) systems facilitate the examination of thermal characteristics spanning semiconductor materials and their associated interfaces. We underscore the significance of meticulous measurements and precise error estimation attained through the analysis of both amplitude and phase data in Thermo-Reflectance (TR). The precision of the analytical estimation hinges greatly on the assumptions made before implementing the method and notably showcases a decrease in errors when both the amplitude and phase are incorporated as input parameters. We demonstrate that frequency-domain calculations can attain high precision in measurements, with error estimations in thermal conductivity (k), thermal boundary resistance (Rth), and thermal diffusivity (α) as low as approximately 2.4%, 2.5%, and 3.0%, respectively. At the outset, we evaluate the uncertainty arising from the existence of local minima when analyzing data acquired via FDTR, wherein both the phase and amplitude are concurrently utilized for the assessment of cross-plane thermal transport properties. Expanding upon data analysis techniques, particularly through advanced deep learning approaches, can significantly enhance the accuracy and precision of predictions when analyzing TR data across a spectrum of modulation frequencies. Deep learning models enhance the quality of fitting and improve the accuracy and precision of uncertainty estimation compared to traditional Monte Carlo simulations. This is achieved by providing suitable initial guesses for data fitting, thereby enhancing the overall performance of the analysis process. [ABSTRACT FROM AUTHOR]

Ultra-thin solar cells display high intrinsic radiation tolerance, making them interesting for space applications. This study investigates the dependence of the open-circuit voltage degradation and overall current–voltage behavior of devices with 80 nm thick GaAs absorber layers, on their absorber layer doping concentration and the radiation type used to introduce damage. The radiation types used were 1 MeV electrons and 20 keV, 100 keV, and 1 MeV protons. It is shown that the open-circuit voltage degradation rate increases with absorber layer doping concentration. This is linked to the increase in trap-assisted tunneling enhancement of the recombination rate, facilitated by the increase in electric field strength in the absorber layer with doping concentration. Trap-assisted tunneling is also found to contribute to the high local ideality factors observed in these devices, exceeding values of 2, and to be responsible for the trend of an increasing ideality factor with doping concentration. The significant role of trap-assisted tunneling in the devices is established through fitting of dark current–voltage data using a custom recombination–generation model. An open-circuit voltage degradation rate and local ideality factor curves are also shown to vary with radiation type, despite accounting for their differences in non-ionizing energy loss. This is corroborated by corresponding trends in carrier lifetime damage constants, extracted from the fitting of the dark current–voltage curves. This suggests that the introduction or behavior of radiation damage differs between ultra-thin and conventional, thicker solar cells, where non-ionizing energy loss theory tends to be reliable, especially over the studied proton energy range. [ABSTRACT FROM AUTHOR]

Asymmetric quantum wells (AQWs) utilizing interband transitions enhance second-order susceptibility over a wide wavelength range compared to natural crystals. The nonlinear susceptibility is further enhanced in AQWs with type-II band alignment as compared to type-I band alignment, a result of the larger interband charge shift. This enhancement is demonstrated in this work by analyzing three type-I and type-II AQW designs based on the lattice-matched InP/AlGaInAs materials systems using the envelope wavefunction approximation. The calculated interband second-order susceptibility tensor elements in type-II structures range between 20 and 1.60 × 103 pm/V for nearly resonant optical rectification and difference frequency generation applications at near-infrared and terahertz wavelengths, an improvement of nearly 1 order of magnitude over the type-I structures and 1–2 orders of magnitude over natural crystals such as LiNbO3, KTiOPO4 (KTP), or GaAs. A factor of 2–3 further enhancement of the tensor elements is achieved by optimizing the well widths and band offsets of the type-II asymmetric quantum wells. The type-II structure can be implemented in other material systems spanning the longwave infrared to visible wavelengths, enhancing nonlinear susceptibility for various applications, including photonic integrated circuits. [ABSTRACT FROM AUTHOR]

The Sn-doping effects on the electrical conduction and optical properties of GaAs(631)A epilayers grown by molecular beam epitaxy were investigated. We found that the conduction type conversion, frequently observed in the doping of layers grown on high-index substrates, is avoided when tin-doping is implemented. The maximum free-carrier concentration (n) obtained in GaAs(631):Sn was 2 × 1019 cm−3, an order of magnitude higher than previously reported for GaAs(631):Si, and within the same order of magnitude for the growth of GaAs(100):Si. The electron mobility was suitable for many optoelectronic applications. Raman spectroscopy showed low lattice disorder in (631) oriented samples, compared with singular (100) samples. The photoluminescence characterization of the samples revealed the blueshift of the optical transitions close to E0 associated with the Moss–Burstein effect for Sn doping. Photoreflectance spectroscopy was used to study the doping properties at the critical points E1 and E1 + Δ1, where the major affectation with n was perceived in the broadening parameter Γ. [ABSTRACT FROM AUTHOR]

We demonstrated the crystal growth of group-III arsenides (III-As) on GaN via an arsenidation layer and GaN-channel electron mobility transistors (HEMTs) with a regrowth InAs/GaAs source and drain (S/D) region. By annealing under an AsH3 atmosphere, the surface of a GaN (0001) template is arsenided. We grew ⟨ 111 ⟩ oriented InAs and GaAs on arsenided GaN. Silicon-doped n-type InAs with a carrier mobility of over 1500 cm2/V s and a carrier concentration of over 1 × 1019 cm−3 was successfully obtained. The fabrication process and direct-current characteristics of GaN-channel HEMTs with the regrown Si-doped InAs/GaAs S/D region were demonstrated for the first time. A maximum transconductance estimated from transfer characteristics was as high as ∼195 mS/mm for the HEMT with a gate length of 2 μm without passivation, which is comparable to those for the HEMT without any S/D regrowth. The impact of the InAs/GaAs S/D region on the on-resistance of the fabricated HEMTs was estimated to be ∼0.9 Ω mm, which can be reduced by optimizing the device structures and process conditions. These results indicate that the process of GaN arsenidation and III-As regrowth can be used without any device performance degradation. Therefore, further lowering the ohmic contact resistivity and on-resistance of GaN-channel HEMTs is possible by maturing the manufacturing-process technology of III-As-contained GaN-channel HEMTs. [ABSTRACT FROM AUTHOR]

A band design of a quantum cascade laser with a generation frequency higher than 6 THz and an active region based on four GaAs/Al0.14Ga0.86As quantum wells is proposed. Calculations were carried out based on the solution of the Schrödinger equation taking into account the dephasing of quantum states, as well as a closed system of balance equations. The temperature dependences of the gain at frequencies of 6.3–6.6 THz were calculated for the proposed quantum cascade laser with a double metal waveguide. Features of the proposed laser structure include two injection quantum wells and the suppression of non-radiative transitions between laser levels. According to calculations, this provides the maximum operating temperature of up to 81 K at 6.4 THz. The results of this study open up the way for quantum cascade lasers based on GaAs/AlGaAs to operate at frequencies above 6 THz. [ABSTRACT FROM AUTHOR]

In this article, we bridge the gap between academia and practice by analyzing and presenting the results of allegations in more than 200 lawsuits against the largest public accounting firms. Our findings are critical as the lawsuits damage the firms' reputations, the credibility of the profession in general, and may result in large monetary losses and loss of clients. We find three key results not found in previous legal research. First, we find that Generally Accepted Accounting Principles (GAAP) issues, especially those focused on valuation, dominate Generally Accepted Auditing Standards (GAAS) issues in the allegations. Second, fraud allegations against the auditors themselves are a significant problem, although often ignored in the fraud literature. Third, the Public Company Accounting Oversight Board (PCAOB) reports on the accounting firms provide an unintended source of information for third parties in future legal allegations against those same firms. [ABSTRACT FROM AUTHOR]

We present a systematic investigation of the optical losses in GaAs photonic crystal cavities with and without embedded self-assembled In(Ga)As quantum dots (QDs) to shed light on additional loss mechanisms related to the presence of the QDs. To clarify the role of the measurement method, we propose an experimental configuration where the optical properties can be evaluated simultaneously through reflection and photoluminescence measurements. Independently of the measurement method, we observe a reduced quality (Q) factor in cavities with embedded QDs when compared to the passive counterparts. Our analysis indicates that these additional losses—about 7 GHz—are unrelated to direct excitonic absorption for the investigated areal QD densities of 175 μ m − 2 . We analyze several mechanisms which could explain our observations and suggest that a possible origin could be unsaturable absorption from midgap defects introduced by the QD growth. [ABSTRACT FROM AUTHOR]

In this study, the degradation behavior of flexible GaInP/GaAs/InGaAs (IMM3J) solar cells and their metamorphic subcells under 1 MeV electron irradiation was investigated. The remaining factors such as short-circuit current density (Jsc), open-circuit voltage (Voc), and maximum power (Pmax) were 95.62, 85.52, and 79.73%, respectively, at an irradiation fluence of 2 × 1015 e/cm2. The spectral responses of the InGaAs and GaAs subcells degraded significantly, and the InGaAs subcell experienced greater degradation than the GaAs subcell after irradiation. In addition, the current-limiting unit was switched from GaInP to InGaAs after irradiation. Defect analysis by deep-level transient spectroscopy (DLTS) revealed that with increasing irradiation fluence, the defects that had the greatest impact on the performance of GaAs subcells were EV + 0.36 and EV + 0.42 eV. For InGaAs subcells, the defects that had the greatest impact on the performance were EV + 0.29 and EV + 0.24 eV. The decrease in the minority carrier lifetime is the main reason for the decrease in the electrical performance of solar cells, and the variation in the effective minority carrier lifetime (τeff) in the subcells with the irradiation fluence was calculated based on the DLTS results. At a fluence of 2 × 1015 e/cm2, the τeff of the GaAs and InGaAs subcells decreased from 2.93 × 10−10 and 9.10 × 10−10 s to 1.56 × 10−11 and 1.60 × 10−12 s, respectively. These results provide a reference for predicting the degradation of short-circuit current and open-circuit voltage of flexible IMM3J. [ABSTRACT FROM AUTHOR]

Most semiconductors exhibit a saturation of free carriers when heavily doped with extrinsic dopants. This carrier saturation or "doping limit" is known to be related to the formation of native compensating defects, which, in turn, depends on the energy positions of their conduction band minimum and valence band maximum. Here, we carried out a systematic study on the n-type doping limit of GaAs via ion implantation and showed that this doping limitation can be alleviated by the transient process of pulsed laser melting (PLM). For n-type doping, both group VI (S) and amphoteric group IV (Si and Ge) dopants were implanted in GaAs. For comparison, p-type doping was also studied using Zn as the acceptor. Implanted dopants were activated by the PLM method, and the results are compared to rapid thermal annealing (RTA). Our results reveal that for all n-type dopants, while implantation followed by the RTA results in a similar saturation electron concentration of 2–3 × 1018 cm−3, the transient PLM process is capable of trapping high concentration of dopants in the substitutional site, giving rise to a carrier concentration of >1019 cm−3, exceeding the doping limit of GaAs. However, due to scatterings from point defects generated during PLM, the mobility of n-type GaAs after PLM is low (∼80–260 cm2/V s). Subsequent RTA after PLM (PLM + RTA) is able to remove these point defects and recover the mobility to ∼1000–2000 cm2/V s. The carrier concentrations of these PLM + RTA samples are reduced but are still a factor of 3 higher than RTA only GaAs. This can be understood as the dopants are already incorporated in the substitutional site after PLM; they are less likely to be "deactivated" by subsequent RTA. This work is significant to the understanding of doping mechanisms in semiconductors and provides a means for device applications, which require materials with ultra-high doping. [ABSTRACT FROM AUTHOR]

The effect of the GaAsP strain-compensating layer on type-II GaAs1−xSbx/InyGa1−yAs was investigated. GaAsSb/InGaAs multiple quantum wells (MQWs) without and with GaAsP strain-compensating layers were grown by molecular beam epitaxy. Increasing Sb or In compositions can extend photoluminescence (PL) emission at longer wavelength along with the highly induced compressive strain in the QWs. The power-dependent PL measured at low temperature reveals the type-II band characteristics of the GaAs1−xSbx/InyGa1−yAs system. A detailed analysis of the experimental data reveals that the GaAsP layers compensate the compressive strain of GaAsSb/InGaAs. The type-II QWs with GaAsP layers, (8 nm) GaAs0.84Sb0.16/(2.5 nm) In0.3Ga0.7As/(10 nm) GaAs0.85P0.15, emits PL at ∼1.1 μm, up to 210 K, while the PL of those strained sample without GaAsP vanishes at lower temperature. In view of the described sample, x-ray diffraction (XRD) analysis along with the simulation shows the validity of the procedure, resulting in nearly matched parameters of QW thicknesses and material compositions—(8.9 nm) GaAs0.835Sb0.165/(2.3 nm) In0.3Ga0.7As/(10.3 nm) GaAs0.85P0.15, with those of the designed QW. The thicknesses of QW from the TEM image, (8.6 nm) GaAsSb/(3.1 nm) InGaAs/(10.1 nm) GaAsP, agree well with the XRD results. [ABSTRACT FROM AUTHOR]

GaAs surfaces require electrical and chemical passivation for semiconductor devices, but in order to have air stable passivation, high temperatures have been previously required in the passivation step. Here, we demonstrate air-stable, ex situ plasma passivation of GaAs using consecutive hydrogen and nitrogen plasmas at room temperature. No pre-clean using deoxidizing wet chemistry or other means is required. The hydrogen plasma step removes surface oxides and As, which leaves a Ga-rich layer that the nitrogen plasma then turns to GaN. The formed GaN layer efficiently passivates the surface. The plasma-passivated GaAs shows upto 5 × room-temperature photoluminescence after 1 year, and room-temperature time-resolved photoluminescence demonstrates robust passivation even after 3 years, both comparisons to similarly aged unpassivated GaAs. Atomic force microscopy was used to confirm that the passivated surfaces can be made smooth enough for microelectronic applications. Grazing incidence x-ray diffraction indicated that the nitride films are amorphous, and energy-dispersive x-ray spectroscopy was used to estimate the nitrogen content. We used a common inductively coupled plasma reactive ion etching system for plasma passivation, thus enabling the rapid adoption of this technique. [ABSTRACT FROM AUTHOR]

We study epitaxial growth, crystal structures, and magnetic properties of Fe–As compound thin films grown on GaAs (111)B substrates at various values of the As4:Fe flux ratio γ, using molecular beam epitaxy. The samples grown at low As4 flux (γ = 0.3, sample A) show mainly a body-centered-cubic (bcc) crystal structure, exhibiting ferromagnetic properties similar to bcc Fe. Meanwhile, the Fe–As samples grown at medium γ (2.7–4.5, sample group B) comprise regions of Ni2In-type FeAs (a hexagonal crystal with lattice constants of a = 0.399 nm and c = 0.536 nm), which are grown at the bottom and interface with the GaAs buffer layer, and a layer of non-stoichiometric FeAs with a DO3 structure (a = 0.522 nm) formed on the top. The DO3-structure FeAs phase contains partially transformed regions, which are characterized by thin stripes in a scanning transmission electron microscopy image. Furthermore, in the sample grown with high γ = 8.5 (sample C), a hexagonal Fe–As crystal with a large in-plane lattice constant (a = 0.691 nm and c = 0.542 nm) and threefold screw axes are observed. None of these crystal structures of Fe–As compounds has ever been reported. While sample C shows no ferromagnetism, the samples in group B exhibit strong ferromagnetism with high Curie temperature TC above 400 K. These new ferromagnetic Fe–As compounds are promising for spintronic device applications. [ABSTRACT FROM AUTHOR]

A study of residual mechanical stresses in the surface layer of the HgCdTe/CdTe/ZnTe/GaAs structure based on the registration of the second harmonic signal characteristics of reflected IR laser radiation from the surface of the studied sample passed through a nonlinear crystal was carried out. It is shown that such a sensitive method makes it possible to obtain information about the anisotropy of the polarization of the reflected radiation, caused by the residual deformation. Observations of the fine structure of the angular sweep of the second harmonic signal suggest a complex structure of residual stresses related to the presence of misoriented areas. The results were compared with data obtained from measurements of the azimuthal dependence of the self-reflected second harmonic signal from the sample surface. [ABSTRACT FROM AUTHOR]

The electrical spin injection and detection in perpendicularly magnetized Mn/Co/n-GaAs junction was investigated using a non-local method. Clear non-local spin-valve signals and Hanle effect signals were observed at 77 K, providing direct evidence of the injection and detection of perpendicularly polarized spins through all electrical methods. The magnitude of the spin-valve signal was one order of magnitude smaller than that observed in a reference sample with an in-plane magnetized CoFe due to the low spin polarization of the ultrathin Mn/Co electrodes. It was found that the spin polarization at the interface between Mn/Co electrode and n+-GaAs had a relatively weak bias-current dependence in contrast to that at CoFe/n+-GaAs interface. The estimated spin lifetime of perpendicular spins injected from the Mn/Co bilayer into n-GaAs was approximately 1.9 ns at 77 K. This value is similar to that of in-plane spins injected from CoFe, indicating that the spin lifetime was not strongly dependent on the spin orientation in the bulk GaAs channel. [ABSTRACT FROM AUTHOR]

The emergence of terahertz (THz) nanoscale resonance metasurface devices represents an innovative method for modulating THz waves by utilizing the intense, high-frequency alternating electric field in THz radiation. However, compared to traditional modulation methods that employ electrical, optical, and other techniques, the potential of these devices still necessitates further exploration. In this work, we achieved THz beam-splitting and field-induced nonlinear frequency shifting functions within a single THz nano-metasurface device. The device consists of single split-ring resonators (s-SRRs) with a nanogap on GaAs substrate. The pattern design based on the Pancharatnam–Berry (P-B) phase principle can split the incident wave into three beams. Meanwhile, its frequency shifting capability, which varies with the E-field, has been thoroughly investigated. The device performance was experimentally evaluated by an angle-resolved THz time-domain spectroscopy (THz-TDS) system and a strong-field THz-TDS system. This device could serve as a promising research platform for integrating THz with nano-optics and holds the potential for ultrafast modulation, offering application prospects in radar, wireless communication, and electromagnetic protection. [ABSTRACT FROM AUTHOR]

Unipolar (sub-cycle) electromagnetic fields are a subject of current interest as a possible useful tool for light–matter interaction studies and applications. We propose, numerically simulate, and experimentally prove a method to produce unipolar terahertz fields by optical gating of conventional bipolar terahertz pulses in a GaAs wafer. In particular, picosecond long unipolar pulses with the electric field strength of ∼ 1 kV/cm were detected by electro-optic sampling at the output of the wafer. [ABSTRACT FROM AUTHOR]

The formation of rolled‐up cylindrical membranes stemming from the strain deformation‐induced delamination of a film‐like nanowires array composed of coalesced GaAs nanowires embedded in AlOx with a buried GaAs/AlAs core‐shell structure is reported. The delamination of the nanowires array film is driven by natural oxidation resulting from prolongated exposure to ambient atmosphere. Investigation of the structural characteristics of the nanowires in the array reveals an analytical description of the oxidation mechanism leading to the formation of the rolled‐up structures. The membrane can easily transfer by simply shaking off the surface membranes of the sample. The cylindrical membranes maintain the optical properties of the core GaAs nanowires surrounded by native oxide. The findings show the prospects for area‐saving and transferable semiconductor devices with advanced nanoscale optical functions. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the impact of audit partners' narcissism on the readability of audit reports for companies listed on the Tehran Stock Exchange (TSE). It examines the effects of narcissism among both lead and review audit partners on the clarity of audit reports, considering the regulatory requirements and auditing practices within the Iranian financial reporting context. Design/methodology/approach: This paper analyzed 2,691 firm-year observations from TSE-listed companies spanning 2011–2023, using ordinary least squares regression. Readability of audit reports was assessed using the FOG index, with the size of partners' signatures serving as a proxy for narcissism. Findings: The findings indicate a significant negative relationship between increased narcissism and audit report readability; higher levels of narcissism correspond with elevated FOG index scores. Narcissism in lead partners notably diminishes readability more than that of review partners. This pattern holds across various robustness checks, including alternative readability metrics, variations in auditor engagement complexity, auditor specialization, subsets of qualified audit reports and considerations for endogeneity. Audit reports for economically significant clients tend to be clearer, suggesting a preference for reputation management over yielding to client pressure. Although no direct link was established between partners' quality and readability, a positive relationship exists between audit firm rank and partners' narcissism. Furthermore, interactions between auditor and CEO narcissism increase report complexity, especially in contentious negotiation scenarios. Despite regulatory advancements such as International Auditing Standard 701, its moderating effects were found to be inconsequential, highlighting the persistent influence of narcissism on audit report outcomes. Originality/value: This research expands the understanding of how auditor personality traits, particularly narcissism, affect audit outcomes. By exploring the influence of narcissism on report readability within the Iranian context, this study fills a notable gap in the literature on emerging markets and non-Western reporting environments, providing valuable insights into global audit practices. [ABSTRACT FROM AUTHOR]

Auditing standards have become a central feature in the world of auditing. One of the primary claims made for International Standards on Auditing (ISAs) is their capacity to reduce the audit expectations gap (AEG), but the gap persists despite the widespread adoption of ISAs. France is an intriguing case site for studying the development and impact of audit standard setting, especially given its reputation as a country for maintaining its own distinctive audit regulatory traditions. Its claimed resistance to Anglo‐American influences, however, is not what stands out in our archival analysis of French audit standard‐setting processes and an accompanying series of interviews with key participants. In contrast, the French audit standard setting emerges as a process that has largely aligned with the spirit of ISAs and adopted a narrow interpretation of the AEG. The presented analysis challenges the operational significance of a claimed French exceptionalism and adds to a growing questioning of the capacity of auditing standard setting to drive fundamental advancement in auditing practice and to meet public expectations. [ABSTRACT FROM AUTHOR]

In 2014, the PCAOB adopted a new auditing standard, AS 18 Related Parties, with the intention of enhancing auditors' performance in auditing related-party transactions (RPTs). Using hand-collected data, we find significant reductions in both firms' restatement risk and their engagement in RPTs following the AS 18 adoption. Such reductions are especially pronounced for smaller firms and firms having RPTs with principals, in which related persons in the counterparty of RPTs are the primary beneficiaries, such as CEOs, board chairs, or primary shareholders. We also find that smaller firms having RPTs with principals tend to pay higher audit fees post-AS 18. Our study responds to the PCAOB's call to assess the economic consequences of AS 18. The findings suggest that AS 18 is associated with improved audit quality and reductions in auditees' opportunistic RPT activities. Data Availability: Data are available from public sources as cited in the article and from the authors upon request. JEL Classifications: M10; M40; M41; M42; M48. [ABSTRACT FROM AUTHOR]

We observed tunable characteristics of optical frequency combs (OFCs) generated from InGaAs/GaAs double quantum wells (DQWs) asymmetric waveguide two-section mode-locked lasers (TS-MLLs). This involves an asymmetric waveguide mode-locked semiconductor laser (AWML-SL) operating at a center wavelength of net modal gain of approximately 1.06 µm, which indicates a stable pulse shape, with the power-current(P-I) characteristic curve revealing a small difference between forward and reverse drive currents in the gain region. Under different operating conditions, the laser exhibits the characteristics of OFCs. And the pulse interval in the timing and the peak interval in the frequency domain show a periodic alternating change trend with the increase in the gain current. This tunable characteristic is reported for the first time. The study demonstrates the feasibility of generating tunable optical combs using a monolithic integrated two-section mode-locked semiconductor laser (MI-TS-MLL). This has important reference value for the application of OFCs generated from MI-TS-MLLs or integrated optical chips. [ABSTRACT FROM AUTHOR]

We report resonant cavity infrared detectors with a peak wavelength of 4.54–4.58 μm that combine external quantum efficiency (EQE) exceeding 70% with spectral bandwidth 20–40 nm and ≤2% EQE at all non-resonance wavelengths between 4 and 5 μm. A 300-nm-thick absorber assures that most of the radiation propagating in the cavity produces photocurrent rather than parasitic loss. The cavity is formed by heterogeneously bonding a midwave infrared (MWIR) nBn detector chip to a GaAs/AlGaAs distributed Bragg reflector, etching away the GaSb substrate, forming mesas with diameter ≈100 μm, depositing a Ge spacer, and then depositing a single-period Ge-SiO2 top mirror. At all temperatures between 125 and 300 K, the responsivity at 150 mV bias exceeds 2.2 A/W and the EQE exceeds 61%. When the thermal background current for a realistic system scenario with f/4 optic that views a 300 K scene is derived from the observed EQE spectra, the resulting specific detectivity D* of 7.5 × 1012 cmHz½/W at 125 K operating temperature is 4.5 times higher than for a state-of-the-art broadband MWIR HgCdTe device. Simulations of the cavity performance indicate that EQE > 90% may be feasible following minimization of parasitic optical loss and maximization of the photocarrier collection efficiency. Potential applications include free space optical communication, chemical sensing, on-chip spectroscopy, and hyperspectral imaging. [ABSTRACT FROM AUTHOR]

This work presents and discusses the extraction of the active dopants density of GaAs layers from the modeling of the bandgap temperature dependence derived from photoluminescence measurements. [ABSTRACT FROM AUTHOR]

Digital technology development provides new opportunities for environmental, social, and governance (ESG) performance research to better evaluate firm ESG performance, improve decision-making efficiency, and enhance firm competitiveness. Therefore, under the background of digital economy, studying digitization mechanisms on ESG performance is of great theoretical and practical significance, which can help firms achieve better sustainable development and create more value for stakeholders. We use 3,827 listed A-share companies in China from 2003 to 2021 as the sample for our empirical research. Results show that digitization significantly improves ESG performance, and this conclusion remains valid after a series of robustness tests. Through mechanism analysis, we find that digitization improves ESG performance through organizational resilience and further reveal that organizational redundancy has a positive moderating effect between organizational resilience and ESG performance. According to our heterogeneity analysis, the marginal effects are stronger among listed firms with high market competition, in the East-Central region, in non-heavily polluting industries, and with standard audit opinions, without significant heterogeneity across the nature of equity. Our research provides a theoretical basis for digitization to drive ESG performance and ideas on how to improve the ESG performance of Chinese companies in the digital era. [ABSTRACT FROM AUTHOR]

Quantum dot solar cells are currently the subject of research in the fields of renewable energy, photovoltaics and optoelectronics, due to their advantages which enables them to overcome the limitations of traditional solar cells. The inability of ordinary solar cells to generate charge carriers, which is prevents them from contributing to generate the current in solar cells. This work focuses on modeling and simulating of Quantum Dot Solar Cells based on InAs/GaAs as well as regular type of GaAs p-i-n solar cells and to study the effect of increasing quantum dots layers at the performance of the solar cell. The low energy of the fell photons considers as one of the most difficult problems that must deal with. According to simulation data, the power conversion efficiency increases from (12.515% to 30.94%), current density rises from 16.4047 mA/cm2 for standard solar cell to 39.4775 mA/cm2) using quantum dot techniques (20-layers) compared to traditional type of GaAs solar cell. Additionally, low energy photons’ absorption range edge expanded from (400 to 900 nm) for quantum technique. The results have been modeled and simulated using (SILVACO Software), which proved the power conversion efficiency of InAs/GaAs quantum dot solar cells is significantly higher than traditional (p-i-n) type about (247%). [ABSTRACT FROM AUTHOR]

This study investigates the growth of gallium arsenide nanowires, using lead as a catalyst. Typically, nanowires are grown through the vapor–solid–liquid mechanism, where a key factor is the reduction in the nucleation barrier beneath the catalyst droplet. Arsenic exhibits limited solubility in conventional catalysts; however, this research explores an alternative scenario in which lead serves as a solvent for arsenic, while gallium and lead are immiscible liquids. Liquid lead easily dissolves in Si as well as in GaAs. The preservation of the catalyst during the growth process is also addressed. GaAs nanowires have been grown by molecular beam epitaxy on silicon Si (111) substrates at varying temperatures. Observations indicate the spontaneous doping of the GaAs nanowires with both lead and silicon. These findings contribute to a deeper understanding of the VLS mechanism involved in nanowire growth. They are also an important step in the study of GaAs nanowire-doping processes. [ABSTRACT FROM AUTHOR]

Copyright of Al Bashaer Economic Journal is the property of Al Bashaer Economic Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper examines the implications of the proposed merger of the Australian Accounting Standards Board (AASB), the Auditing and Assurance Standards Board (AuASB) and the Financial Reporting Council (FRC) into a single entity. The merger is designed to improve efficiency, consistency and the adoption of new sustainability standards. During a panel discussion at the AFAANZ Annual Conference, experts analysed the potential impact of the merger on standard‐setting practices, highlighting the need for robust justification and increased transparency. The study highlights the complex interplay of regulatory, national and international contexts shaping this remarkable restructuring. [ABSTRACT FROM AUTHOR]

Copyright of Journal of International Business Studies is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

SYNOPSIS: Auditing standards require auditors to conduct fraud inquiries as part of their risk assessment process. During fraud inquiries, auditors frequently ask client personnel directly about "fraud, alleged fraud, or suspected fraud," using standard language taken from AS 2110. However, guidance from the Center for Audit Quality (CAQ) suggests that avoiding the word "fraud" results in greater disclosure regarding fraud risk. Although untested, the CAQ's conjecture is supported by literature in psychology and criminology, which suggests that minimizing the seriousness of the offense (i.e., minimization) increases disclosure. This study examines two minimization strategies. The first involves replacing the word "fraud" with "questionable behavior." The second employs social comparison to increase the perceived frequency that clients report misconduct to auditors. Experimental results suggest that either strategy increases client reporting intentions relative to a control condition using the language prescribed by AS 2110. Our findings may help auditors conduct more effective fraud inquiries. Data Availability: Data are available from the authors. JEL Classifications: M42; M48. [ABSTRACT FROM AUTHOR]

The on‐chip resonant excitation of single quantum dots (QDs) via integrated microlasers represents an effective and scalable method for integrated quantum photonics applications based on on‐demand single‐photon emitters. In this study, the design and numerical optimization of the evanescent coupling between whispering gallery modes (WGMs) of a micropillar resonator and a nearby single‐mode ridge waveguide in the Al(Ga)As/GaAs material system are presented. In this study, such systems are examined within a wavelength range of 930 nm, which is suitable for resonant excitation of typical self‐assembled InGaAs quantum dots. In particular, the coupling and the transmitted optical power of a WGM resonator to a ridge waveguide are examined for a range of gap spacings, with the objective of optimizing the photon coupling efficiency and Q‐factor of the monolithically integrated nanophotonic system. The findings of this study enable to identify the best device parameters for subsequent device fabrication. The findings establish a foundation for the production of highly effective photonic quantum circuits through the use of WGM microlasers integrated into evanescently coupled waveguide systems, including resonantly excited single quantum dots. [ABSTRACT FROM AUTHOR]

The sustainable development goals (SDGs) are recognized as global development guidelines for 2030. The accounting profession can contribute to achieving these goals by encouraging reporting on SDGs at the company level. The increasing awareness of the contribution of businesses to the achievement of the SDGs is one of the reasons for the improvement in the practice of reporting by companies. This research is secondary data‐based accounting research that aims to analyze the quality of reporting on SDGs and whether coercive pressures in the form of regulatory quality, sustainability regulations, and the strength of audit and reporting standards were determinants of the quality of reporting on SDGs in the era of the COVID‐19 pandemic. The results of this study show that, on average, companies reported on 10 of the SDGs (56% of the 17) during the COVID‐19 pandemic. Further, this study found that coercive pressures in the form of regulatory quality, sustainability regulations, and the strength of audit and reporting standards positively affected the quality of reporting at the country and company levels. These results may imply that reporting on SDGs in the pandemic era was defensive reporting that sought to maintain legitimacy and was mainly driven by formal pressures. [ABSTRACT FROM AUTHOR]

This paper examines the effect of adopting the International Standard on Auditing (ISA) 570 on going concern (GC) disclosures in the audit report in a European environment characterized by low litigation and reputation risk. We exploit a natural experiment in Belgium, where the global GC standard ISA 570 replaced the local GC standard. We examine whether this shift in standards changed the accuracy of auditors' GC disclosures. Using a sample of 30,339 stressed private companies with audited financial statements for periods ending on or after 15 December 2012 till 14 December 2016, our findings suggest that the adoption of the ISA 570 improves the accuracy of auditors' GC disclosures. Specifically, we find that the implementation of the ISA 570 is associated with an 8 percent decrease in false positive misclassifications (GC opinion without subsequent bankruptcy), while the rate of false negative misclassifications (bankruptcy without prior GC opinion) remains unchanged. [ABSTRACT FROM AUTHOR]

III–V‐based multijunction solar cells have become the leading power generation technology for space applications due to their high power conversion efficiency and reliable performance in extraterrestrial environments. Thinning down the absorber layers of multijunction solar cells can considerably reduce the production cost and improve their radiation hardness. Recent advances in ultrathin GaAs single‐junction solar cells suggest the development of light‐trapping nanostructures to increase light absorption in optically thin layers within III–V‐based multijunction solar cells. Herein, a novel and highly scalable nanosphere lithography‐assisted chemical etching method to fabricate light‐trapping nanostructures in InGaP/GaAs dual‐junction solar cells is studied. Numerical models show that integrating the nanostructured Al2O3/Ag rear mirror significantly enhances the broadband absorption within the GaAs bottom cell. Results demonstrate that the light‐trapping nanostructures effectively increase the short‐circuit current density in GaAs bottom cells from 14.04 to 15.06 mA cm−2. The simulated nanostructured InGaP/GaAs dual‐junction structure shows improved current matching between the GaAs bottom cell and the InGaP top cell, resulting in 1.12x higher power conversion efficiency. These findings highlight the potential of light‐trapping nanostructures to improve the performance of III‐V‐based multijunction photovoltaic systems, particularly for high‐efficiency applications in space. [ABSTRACT FROM AUTHOR]

This paper presents a novel method for nonlinear modeling GaAs field‐effect transistors (FETs) in a common gate (CG) configuration, which is crucial for the effective design and thorough assessment of RF switch circuits. By focusing solely on a CG‐based GaAs FET for RF switch device characterization and modeling, the modeling process is streamlined compared to traditional methods that involve both CG and common source (CS) devices. The direct measurement of both DC and RF characteristics using the CG device enhances the accuracy of model parameter extraction. This approach ensures consistency in model and simulation applications as the CG topology aligns with devices commonly found in RF switch circuits. Moreover, to enhance predictive accuracy regarding the dispersion effect, an improved equation of drain‐source current has been incorporated. The empirical validation of the model reveals good agreements in terms of insertion loss, isolation, and output power performance for the CG GaAs FET device, including a wide band single‐pole double‐throw (SPDT) switch Monolithic Microwave Integrated Circuit (MMIC). [ABSTRACT FROM AUTHOR]

This study examines the excitation of transverse optical phonons in a semiconductor sample under the action of electromagnetic pulses of arbitrary duration, in view of their passage through the interface and absorption in matter. A universal formula for the total absorption coefficient through the components of the complex refractive index of the medium is derived. The dependences of phonon excitation efficiency on the sample thickness and excitation pulse parameters are examined using the example of a GaAs sample and pulses with Gaussian envelope. The specific features of the considered process are established for the carrier frequencies of the pulse inside and outside the photonic forbidden zone. [ABSTRACT FROM AUTHOR]

The first part of this work evaluates Al-doped ZnO (AZO) as an optically transparent top-gate material for studies on semiconductor quantum dots. In comparison with conventional Ti gates, samples with AZO gates demonstrate a more than three times higher intensity in the quantum dot emission under comparable excitation conditions. On the other hand, charges inside a process-induced oxide layer at the interface to the semiconductor cause artifacts at gate voltages above  U ≈  1 V. The second part describes an optical and simulation study of a vertical electric-field (F)-induced switching from a strong to an asymmetric strong–weak confinement in GaAs cone-shell quantum dots (CSQDs), where the charge carrier probability densities are localized on the surface of a cone. These experiments are performed at low U and show no indications of an influence of interface charges. For a large F, the measured radiative lifetimes are substantially shorter compared with simulation results. We attribute this discrepancy to an F-induced transformation of the shape of the hole probability density. In detail, an increasing F pushes the hole into the wing part of a CSQD, where it forms a quantum ring. Accordingly, the confinement of the hole is changed from strong, which is assumed in the simulations, to weak, where the local radius is larger than the bulk exciton Bohr radius. In contrast to the hole, an increasing F pushes the electron into the CSQD tip, where it remains in a strong confinement. This means the radiative lifetime for large F is given by an asymmetric confinement with a strongly confined electron and a hole in a weak confinement. To our knowledge, this asymmetric strong–weak confinement represents a novel kind of quantum mechanical confinement and has not been observed so far. Furthermore, the observed weak confinement for the hole represents a confirmation of the theoretically predicted transformation of the hole probability density from a quantum dot into a quantum ring. For such quantum rings, application as storage for photo-excited charge carriers is predicted, which can be interesting for future quantum photonic integrated circuits. [ABSTRACT FROM AUTHOR]

The use of conductive and corrosion-resistant protective layers represents a key strategy for improving the durability of light absorber materials in photoelectrochemical water splitting. For high performance photoanodes such as Si, GaAs, and GaP, amorphous TiO2 protective overlayers, deposited by atomic layer deposition, are conductive for holes via a defect band in the TiO2. However, when coated on simply prepared, low-cost photoanodes such as metal oxides, no charge transfer is observed through amorphous TiO2. Here, we report a hybrid polyethyleneimine/TiO2 layer that facilitates hole transfer from model oxides BiVO4 and Fe2O3, enabling access to a broader scope of available materials for practical water oxidation. A thin polyethyleneimine layer between the light absorber and the hybrid polyethyleneimine/TiO2 acts as a hole-selective interface, improving the optoelectronic properties of the photoanode devices. These polyethyleneimine/TiO2 modified photoanodes exhibit high photostability for solar water oxidation over 400 h. This study presents a hybrid polyethyleneimine/TiO2 protective layer as a low-cost photoanode for solar water oxidation. The hybrid layer facilitates hole transfer from the photoanode and results in high photostability over 400 hours. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to examine how the allocation of audit hours to the year-round procedures, based on the risk of material misstatements in financial statements, impacts audit quality. Design/methodology/approach: Using a data set on audit hours spent on year-round and year-end procedures, the authors build an empirical model for testing the effectiveness of year-round auditing of Korean public firms during the period of 2014–2018. Findings: The initial tests do not show that proportionate increases in year-round procedures increase audit quality. However, after the authors control for the risk of material misstatements, the authors find that proportionate increases in year-round audit hours generally increase audit quality, except for high-risk firms where audit quality increases only as year-end hours proportionately increase. For high-risk firms, the results suggest that increases in year-round audit procedures occur at the cost of the essential year-end work. Similarly, except for high-risk firms, the authors find that the allocation of more audit effort to year-round procedures improves audit efficiency. Originality/value: To the best of the authors' knowledge, this study provides some of the first empirical evidence showing how a risk-based approach to allocating audit effort over the duration of an audit can impact audit quality and efficiency. Regulatory bodies, such as the International Auditing and Assurance Standards Board and Public Company Accounting Oversight Board, which consider the proper allocation of audit hours as a key audit quality indicator, should find the results useful. [ABSTRACT FROM AUTHOR]

This study aims to respond to the new auditing standard on the information reporting of Key Audit Matters (KAMs) as a separate section in the auditor's report, which will increase the transparency and quality of the report. It not only explores the current practice of KAM reporting among Thai listed companies but also seeks factors that influence KAM reporting in Thailand. This study explores the quantitative methodology through secondary data collected from the Thai Stock Exchange. This archival research explores 343 listed companies in the Thai Stock Exchange from 2016 to 2020. Descriptive statistics, a correlation matrix, and regression analysis are employed. The results suggest that the type of auditor (Big 4 or non-Big-4 audit firms), audit fee, audit independence, and industry have a direct positive impact on Key Audit Matter reporting at a 0.05 significance level. However, the evidence also suggests that the presence of females on the board, year, ROA (return on asset), risk, and size were not validated factors that have direct positive impacts on Key Audit Matter reporting at a 0.05 significance level. [ABSTRACT FROM AUTHOR]

We investigated the single-electron spectrum of an InAs/GaAs quantum dot (QD) using an effective potential model developed in previous studies. Our objective was to explore the limits of applicability of this model. We conducted numerical simulations, introducing a piezoelectric potential as a perturbation to the effective potential. The profile of this additional potential was derived from theoretical numerical studies presented in the literature. We analyzed the impact of variations in this profile within the framework of the perturbation theory. Our findings indicate that within a variation range of 25%, the effective potential model remains applicable. [ABSTRACT FROM AUTHOR]

This series of three exercises engages students with experiential learning related to the PCAOB's unqualified auditor's report on financial statements. The case can be facilitated either in the classroom or online and is easily customizable for undergraduate and graduate audit courses. The case can provide a 20-minute introduction of the auditor's report to an entire class period filled with exercises covering different aspects of audit opinion reporting and discussing an ethical decision-making process. During the first two exercises, students analyze auditor's reports to detect deviations from the PCAOB standard unqualified auditor's report. During the third exercise, students use the Giving Voice to Values (GVV) approach to plan a strategy for correcting an auditor's report error, despite their audit manager's initial instructions to ignore the issue. By applying the GVV ethical decision-making framework in an auditor decision context, the case prompts students to infer and consider different stakeholders' incentives and biases. Data Availability: Data are available upon request. [ABSTRACT FROM AUTHOR]

Utilizing text analysis through machine learning techniques, this study investigates the influence of enterprise digital transformation on audit opinions within China's A‐share listed companies spanning from 2011 to 2020. The findings underscore that enterprise digital transformation has the potential to bolster standard unqualified audit opinions through the enhancement of internal control quality and information transparency. Additionally, factors such as marketization level, property rights nature, and industry classification are found to be pivotal in shaping this relationship. These research outcomes not only extend the theoretical horizons of audit opinion studies but also offer valuable insights and recommendations for auditors to optimize the efficacy of audit opinions. [ABSTRACT FROM AUTHOR]

N-type doping in GaAs is a self-limited process, rarely exceeding a carrier concentration level of 1019 cm−3. Here, we investigated the effect of intense pulsed light melting on defect distribution and activation efficiency in chalcogenide-implanted GaAs by means of positron annihilation spectroscopy and electrochemical capacitance–voltage techniques. In chalcogenide-doped GaAs, donor–vacancy clusters are mainly responsible for donor deactivation. Using positrons as a probe of atomic scale open volumes and DFT calculations, we have shown that after nanosecond pulsed light melting the main defects in heavily doped GaAs are gallium vacancies decorated with chalcogenide atoms substituting As, like VGa–nTeAs or VGa–nSAs. The distribution of defects and carriers in annealed GaAs follows the depth distribution of implanted elements before annealing and depends on the change in the solidification velocity during recrystallization. [ABSTRACT FROM AUTHOR]