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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]

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]

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]

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]

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]

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]

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]

The Q resolution in Bonse–Hart double‐crystal diffractometers is determined for a given Bragg angle by the value of the crystallographic structure factor. To date, the reflections Si 220 or Si 111 have been used exclusively in neutron scattering, which provide resolutions for triple‐bounce crystals of about 2 × 10−5 Å−1 (FWHM). The Darwin width of the GaAs 200 reflection is about a factor of 10 smaller, offering the possibility of a Q resolution of 2 × 10−6 Å−1 provided crystals of sufficient quality are available. This article reports a feasibility study with single‐bounce GaAs 200, yielding a Q resolution of 4.6 × 10−6 Å−1, six times superior in comparison with a Si 220 setup. [ABSTRACT FROM AUTHOR]

Less complex entities (LCEs) make a critical contribution to the public, private and voluntary sectors in England and internationally and account for the great majority of all local public audits. Recently, the role and objectives of financial reporting and external auditing in England have been subject to unprecedented criticism through a number of independent national reports. This paper discusses the auditing arrangements for LCEs in the public sector in England by examining the evidence generated by the local public audit review by Sir Tony Redmond. It discusses implications for the local public audit regime and considers whether the existing and proposed accountability and transparency arrangements are compatible with the new International Standard on Auditing (ISA) for LCEs. It contributes to the limited research on the new ISA for LCEs by investigating the differences and similarities between the new ISA for LCEs and the emerging auditing standards for English LCEs. [ABSTRACT FROM AUTHOR]

This study investigates the work of actually writing auditing standards in France, a country that has not adopted the International Standards on Auditing (ISAs). Based on interviews, participant observation, and documentary study, I highlight the adaptation work carried out to develop French standards, with a transposition mechanism that goes far beyond simply translating ISAs. I emphasise the significant impact of legalism and the principle of hierarchy of norms. I also illustrate the writing conventions used to set standards that are clear and understandable for a wide range of stakeholders. My results show that every word counts in standard‐setting work, which makes it an iterative process involving experts in standard‐setting technique. This study opens the black box of standard‐setters' work and offers a new perspective for analysis of standard setting by considering it as a writing process. [ABSTRACT FROM AUTHOR]

This study examines the effects of COVID‐19 and the enhanced internal control requirements (Korea Sarbanes‐Oxley or K‐SOX) on audit effort in Korea. The results show that both COVID‐19 and K‐SOX led to increases in audit effort. Regarding the comparative magnitude of these two shocks, COVID‐19 is associated with greater total audit effort, whereas K‐SOX is linked to greater IT audit effort. This study also finds that Big 4 firms negatively moderate the increase in total audit effort and IT audit effort caused by COVID‐19. Additionally, Big 4 firms moderate the effect of K‐SOX on mid‐sized clients. Specifically, Big 4 firms positively moderate the increase in total audit effort, whereas they negatively moderate the increase in IT audit effort caused by K‐SOX. This study also investigates the effects of COVID‐19 and K‐SOX on various ranks of auditors and the effects of these exogenous events observed across different industry sectors. Our findings provide insights into the impact of an unpredicted global health crisis and predicted stringent regulations on audit effort when they occur simultaneously, an area that has never been addressed due to its unprecedented nature. [ABSTRACT FROM AUTHOR]

The United Nations has set up 17 sustainable development goals (SDGs) to be achieved by 2030. This research investigates the role of management system standards and multinational supply chains in achieving SDGs and targets, as well as whether these two paths produce varying degrees of effectiveness in achieving these goals. Questionnaire‐based research is conducted among 264 Indian manufacturing organisations based on their certification status and MNE supplier status. Comparison of the surveyed organisations is carried out on three parameters, namely, number of targets for each SDG, fulfilment levels of these targets and extension of established targets further in the supply chain. Analysis of variance and t‐test methods are used to compare survey responses. Results show that the role of management system standards and auditing frameworks used by multinational enterprises is statistically similar in achieving SDGs. The role of management system standards in achieving each of the SDGs has not yet been attempted so far by using the aforementioned factors. The comparison of management system standards' auditing approaches with the auditing frameworks of multinational enterprises also provides a novel addition. Both multinationals and their supplier organisations can save time, money and effort by following either of the two approaches and avoiding the duplicity that is currently prevalent in practice. The research has theoretical implications for sustainability, modernisation and globalisation theories. [ABSTRACT FROM AUTHOR]

The International Auditing and Assurance Standards Board (IAASB) issued for public comment Proposed International Standard on Auditing 570 (Revised) Going Concern. The Australian Auditing and Assurance Standards Board (AUASB) and New Zealand Auditing and Assurance Standards Board (NZAuASB) also called for comments. The Auditing and Assurance Standards Committee of AFAANZ prepared a submission, based on the findings reported in extant research, informing a number of the questions asked by the IAASB. This technical note presents the formal submission made to the IAASB. [ABSTRACT FROM AUTHOR]

This study explores how strength auditing and reporting standards (SARS) and country‐level governance interplay to reduce money laundering. The empirical study is based on a panel dataset of 109 countries, over the period 2012–2019. To test our hypotheses, relevant statistical techniques are used to enhance the robustness of the models. The empirical results reveal that the interaction between SARS and country‐level governance affect significantly and negatively money laundering. Additionally, through dynamic analysis we found that SARS and country‐level governance affect jointly Money laundering level, which confirm the complementarity between the two mechanisms. Money laundering is a worldwide phenomenon that threatens the stability of economies. Consequently, the regulatory bodies and international organization should improve auditing and reporting standards as well as governance practices at different levels (macro, micro, and mezzo). [ABSTRACT FROM AUTHOR]

Semiconductor nanowires have inspired plenty of novel nanotechnology device concepts in photonics, electronics, and sensing, owing to their unique functionalities and integrability in heterogeneous platforms. Lattice‐mismatched core/shell heterostructures, in particular, open new avenues for strain engineering and material properties modification. A notable case is the widely tunable tensile strain in the core of GaAs/InxAl1‐xAs core/shell nanowires, which can be used to tailor the GaAs bandgap for applications across near‐infrared, like optical fiber telecommunication, imaging, photovoltaics, etc. As it is shown here, though, the bandgap narrowing under high tensile strain in the GaAs core is accompanied by fast non‐radiative recombination, which is undesirable for any device application. The limiting role of the lattice‐mismatched core/shell interface is revealed, and a novel core/dual‐shell heterostructure that employs an intermediate AlyGa1‐yAs shell (spacer) is proposed. This spacer decouples the GaAs/AlyGa1‐yAs interface, which confines electrons and holes into GaAs, from the lattice‐mismatched AlyGa1‐yAs/InxAl1‐xAs one, whereas the strain in GaAs is unaffected. Choosing the optimal spacer thickness, the photoluminescence yield increases significantly, with longer emission decay lifetimes and slower carrier cooling rates. Besides unlocking the potential of GaAs for photonic applications across near‐infrared, the proposed heterostructure concept can also be adopted for other material systems. [ABSTRACT FROM AUTHOR]

This article centers its attention on the phenomenon of electrostatics, linearity, analogue, and RF performance of a 0.5 μm × (2 × 100) μm double heterojunction AlGaAs/InGaAs/GaAs pHEMT using on‐wafer DC and RF measurements up to 50 GHz. With a high ION/IOFF ratio (1.21 × 107) and low subthreshold slope (72.7 mV/dec), a flat and high transconductance over a wide range of Vgs has been achieved for the tested device. Furthermore, the input intercept and higher‐order voltage intercept point both attained large values with low intermodulation and harmonic distortion. Regarding RF parameters, the intrinsic gain has been achieved up to 28 dB. The GBW up to 750 GHz was attained, with the highest fT and fmax values being 24.5 GHz and 99.3 GHz, respectively. Since the device has very low intrinsic capacitance, parameters like TFP, GFP, and GTFP also showed excellent results. The high intrinsic gain and TGF indicate ample potential of the device for use as an amplifier. Investigating the parameters reveals the device to have very good linearity and amplifying capability. [ABSTRACT FROM AUTHOR]

In order to address the challenges of complex process and low precision in traditional device modeling, double hidden layer back propagation neural network (BPNN) are trained using the conjugate gradient (CG) algorithm and the Levenberg–Marquardt (LM) algorithm, the CG‐BPNN and LM‐BPNN models of small signal for gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) are obtained and analyzed here. At first, the scattering parameters (S‐parameters) of GaAs pHEMT are divided into training set and test set randomly. Experimental results show that the CG‐BPNN model is better than another S‐parameters when predicting ImS12 with mean square error (MSE) of 7.6632e‐06, while LM‐BPNN model predicts ImS12 with MSE of 2.4672e‐06. Meanwhile, the MSE of CG‐BPNN model is higher than LM‐BPNN model when predicting all the S‐parameters. In addition, it shows a smaller fluctuation range for the error curve of LM‐BPNN model, which is more stable than the CG‐BPNN model. Therefore, the double hidden layer LM‐BPNN model is the better choice to characterize the small signal of GaAs pHEMT. [ABSTRACT FROM AUTHOR]

Midinfrared photonic devices are used as lasers and photodetectors in optical gas sensors and fiber‐optic communications. Herein, the pair number dependence and strain compensation dependence of the InAsSb/InAsP superlattice structure to increase luminescence intensity and reduce crystal defects is investigated. InAs substrates are used to demonstrate various effects of strain compensation, including its role in increasing luminescence intensity and improving the surface flatness. Furthermore, the photoluminescence spectra of a grown superlattice between the InAs substrate and GaAs substrate with two‐temperature‐step growth are shown. [ABSTRACT FROM AUTHOR]

Herein, time‐integrated and time‐resolved photoluminescence (PL) measurement experiments are performed on coupled GaAs quantum dot (QD) molecules with larger laser spot size and a single‐coupled QD molecule to investigate the dynamics of exciton states. A linearly polarized laser along the coupled direction of a laterally‐coupled GaAs QD molecule [11¯$\overset{\cdot}{1}$0] is used to determine the coupling effects of the different exciton states. For the ensemble of coupled QD molecules, the exciton PL peak shifts to lower energy (≈70 meV) and shows a linear increase in the PL intensity, demonstrating the properties of exciton states as a function of the laser excitation power. In addition, a power‐dependent redshift is observed in the single‐coupled GaAs QD molecule as a function of the excitation power; however, the two distinguished exciton states become resolved and show different power factors when the laser excitation power is linearly increased. This result clearly indicates the presence of energy transfer between the two different exciton states, X1 and X2. Furthermore, when the polarized laser excitation power is increased, a coupled biexciton consisting of two different localized exciton states (X1 and X2) is clearly observed, and a power‐dependent spectral redshift is detected in the exciton and biexciton states. At a high excitation power (15 I0), the decay times of the two different localized exciton states clearly show different lifetimes; and the decay time difference due to the size difference can be ignored at a low excitation power. Theoretically, the decay times of the two different exciton states, wherein the size deviation can be ignored, should be the same. Based on the results of the time‐integrated and time‐resolved PL measurements and the comparison between the ensemble and single exciton PL peaks, it is concluded that the coupling process in laterally‐coupled GaAs QD molecules is strongly supported against long‐range separation. [ABSTRACT FROM AUTHOR]

Ultrathin GaAs solar cells have gained attention because they are cost‐effective and exhibit high carrier‐collection efficiency and open‐circuit voltage compared with cells with thicker absorber layers. However, ultrathin GaAs solar cells have a low current density due to their thin light‐absorbing layers. To improve the photoabsorption of ultrathin GaAs solar cells, light‐trapping structures with textured front or rear surfaces are necessary, and easy methods for fabricating textured structures are required. In this study, a new method to create light‐scattering textured surfaces using block copolymers is developed. This method only requires spin coating, annealing, and wet etching, making it easily applicable to large‐area devices such as solar cells. An ultrathin GaAs solar cell is fabricated with a rear‐textured structure using block copolymers as masks for wet etching. The results demonstrate that the short‐circuit current density is enhanced by 1.39 mA cm−2, which improves the energy conversion efficiency by 0.71 percentage points compared with a reference cell without a rear‐textured structure. [ABSTRACT FROM AUTHOR]

Although auditing standards instruct auditors to avoid issuing standardised key audit matters (KAMs), standard setters warn and financial statement users worry about expanded auditor's reports becoming sticky, generic and boilerplate over time. Based on textual analysis of expanded auditor's reports from the UK, I provide longitudinal evidence of an increase in various textual similarity measures including year‐over‐year similarity (stickiness), within‐peer group similarity (generality) and boilerplate language over time. Next, I identify a number of crucial drivers of convergence and find that disclosure similarity diminishes the positive capital market effect of precise KAM reporting documented in prior studies. Together, these findings suggest that audit firms have successively developed standard text modules for KAM reporting that undermine the aim of expanded auditor's reports to provide informative value. This paper extends the literature on the relationship between institutional environments and unintended effects of auditor disclosure regulation. [ABSTRACT FROM AUTHOR]

This study explores the impact of integrating a gallium arsenide (GaAs) pocket at the source and drain in a dual‐material gate‐oxide‐stack double‐gate tunnel field‐effect transistor (DMGOSDG‐TFET). The performance of this DMGOSDG‐TFET, employing work‐function engineering and gate‐oxide‐stack techniques, is compared with a GaAs pocket‐doped DMGOSDG‐TFET. Using the Silvaco Technology Computer‐Aided Design tool, the comparison covers DC characteristics, analog/RF behavior, and circuit‐level assessments. The research introduces an optimized heterostructure pocket‐doped DMGOSDG‐TFET to enhance DC characteristics, analog/RF performance, and DC/transient analysis. This novel architecture effectively suppresses ambipolarity, making it more suitable for current conduction. The incorporation of work‐function engineering and a gate‐oxide‐stack approach enhances the device's current driving capability, while the use of a highly doped GaAs pocket at the source and drain virtually eliminates ambipolar current conduction. Simulation results indicate that the proposed heterostructure device exhibits a high ON‐current and switching ratio. For analog/RF applications, the optimized heterostructure device outperforms conventional DMGOSDG‐TFET, offering higher cutoff frequency, transconductance, and other analog/RF parameters. Circuit‐level performance is assessed using HSPICE, with a focus on the implementation of a resistive‐load inverter for both proposed and conventional device topologies through DC and transient evaluations. [ABSTRACT FROM AUTHOR]

Drawing on institutional and signaling theories, this paper investigates country‐and firm‐level impact of Sustainable Development Goals (SDGs) on the European Union (EU) companies' decision to have sustainability reporting assured prior to the implementation of the Corporate Sustainability Reporting Directive (CSRD). The dataset consists of 960 companies based in the EU and covers 2020–2022. The total number of observations equals 2880. The research focuses on SDGs‐related factors influencing companies' assurance decisions such as the countries' advancement in SDGs implementation represented by SDG SCORE and companies' efforts toward the SDGs achievement captured with SDG INDEX. The data are analyzed using descriptive statistics and the fixed effects regression model for panel data. The results of the study indicate that SDGs impact companies' assurance decisions on both levels. Larger companies tend to opt for assuring their sustainability reporting more frequently, while those operating in environmentally sensitive industries display greater hesitancy in this regard. The research findings suggest adding SDGs to the wide range of factors identified in previous literature as determinants of the differences in sustainability reporting assurance. Company managers should increase their efforts to achieve the SDGs, as this might promote the use of assurance. The involvement of government agencies, national accounting and auditing associations and standard setters in the implementation of the SDGs can be useful in facilitating the transition from voluntary to mandatory implementation of assurance under the new CSRD. [ABSTRACT FROM AUTHOR]

This study examines the impact of the Financial Reporting Standard No. 44 New Zealand Additional Disclosures (FRS 44) amendment issued by the New Zealand Accounting Standards Board (NZASB). The FRS 44 amendment aligned disclosure requirements for managerial assessments of going concern risk in financial reports with auditing standards for periods ending on or after 30 September 2020. We first present descriptive evidence on the frequency of going concern opinions (GCO), frequency of going concern issues identified as key audit matters (GCKAM), and frequency and content of managerial assessments of going concern risk (GCMA) before and after the FRS 44 amendment. Second, we show lower audit fees and shorter audit lags for financially distressed companies post‐FRS 44 implementation. This suggests that the harmonisation of accounting and auditing disclosure requirements alleviates tension during the going concern decision‐making process for affected companies, subsequently leading to reduced audit fees. [ABSTRACT FROM AUTHOR]

Many III–V semiconductors possess direct bandgaps and are thus widely applied in optoelectronics. Although GaN (either in wurtzite phase or zinc blende phase), GaAs, and GaSb are well‐known direct‐gap semiconductors, GaP exhibits an indirect bandgap nevertheless. In this work, the generic rule of energy gaps in GaN, GaP, and GaAs of the zinc blende phase is analyzed, and the trends of gap variation are studied concerning the lattice constant and anion electronegativity. It turns out that GaP actually manifests a normal behavior, the reason why GaN surprisingly has a direct gap is analyzed through examining and perturbing its valence band as well as conduction band (CB). The CB electron shows a non‐negligible probability to emerge near the N cores. The attractive nucleus potential pulls down the CB more strongly at Γ, which is in principle further supported through an analysis of the Kronig–Penney model. The difference between GaP and GaN in this respect is also analyzed in detail. [ABSTRACT FROM AUTHOR]

The aim of this work is to minimize reflection losses in order to increase the efficiency of solar cells by using anti‐reflection coatings (ARCs). Despite extensive research on improving solar cell conversion efficiency at normal incidence, development at angle of incidence has received little attention. Thus, the reflectivity of single‐layer ARC (SLARC) MgF2 and ZnSe, double‐layer ARC (DLARC), MgF2/ZnSe on Si, and GaAs substrates at transverse electric (TE) and transverse magnetic (TM) modes of polarization in the visible and near‐IR regions for different angles of incidence is analyzed. The optical and electrical properties of Si and GaAs solar cells are analyzed by using the reflectance spectra of SLARC and DLARC at various angles of incidence for the TM and TE modes of polarization under the solar power spectrum (AM1.5). The achieved results due to the effect of DLARC are compared for Si and GaAs solar cells. From these analyses, it is concluded that MgF2/ZnSe is an appropriate DLARC for the range of wavelengths 400–800 nm at 10°–30° angles of incidence in TM mode for tuning the optical and electrical properties of Si and GaAs substrates for terrestrial applications. [ABSTRACT FROM AUTHOR]

Herein, the crystal phase switching between the cubic zinc‐blende and hexagonal wurtzite phases in self‐catalyzed GaAs nanowires (NWs) is theoretically studied, considering the dependence of the droplet contact angle on the position at the triple‐phase line. This dependence is calculated for the droplets resting on the NW top facet, which has the shape of truncated hexagon. The nucleation of c and h islands, corresponding to the cubic and hexagonal crystal phases, at the triple‐phase line and in the center of the catalyst–NW interface, is considered within the classical nucleation theory. As a result, the probability of h‐island nucleation as a function of the average contact angle is obtained. It is found that the maximum of this probability shifts to the region of large contact angles when the length of narrow edges of the NW top facet decreases. Also, it is shown that the GaAs island nucleation at the triple‐phase line occurs preferentially in the vicinity of the top facet corners. [ABSTRACT FROM AUTHOR]

Receiver and transmitter monolithic microwave integrated circuit (MMIC) multifunction chips (MFCs) for active phased‐array antennas for Ka‐band satellite communication (SATCOM) terminals have been designed and fabricated using a 0.15‐μm GaAs pseudomorphic high‐electron mobility transistor (pHEMT) process. The MFCs consist of four‐channel radio frequency (RF) paths and a 4:1 combiner. Each channel provides several functions such as signal amplification, 6‐bit phase shifting, and 5‐bit attenuation with a 44‐bit serial‐to‐parallel converter (SPC). RF pads are implemented on the bottom side of the chip to remove the parasitic inductance induced by wire bonding. The area of the fabricated chips is 5.2 mm × 4.2 mm. The receiver chip exhibits a gain of 18 dB and a noise figure of 2.0 dB over a frequency range from 17 GHz to 21 GHz with a low direct current (DC) power of 0.36 W. The transmitter chip provides a gain of 20 dB and a 1‐dB gain compression point (P1dB) of 18.4 dBm over a frequency range from 28 GHz to 31 GHz with a low DC power of 0.85 W. The P1dB can be increased to 20.6 dBm at a higher bias of +4.5 V. [ABSTRACT FROM AUTHOR]

Real‐time audit is the auditing of actions as they occur and the publishing of findings before the audited action was completed. It is an emerging practice of Supreme Audit Institutions (SAIs) in many countries, and it marks a stark departure from the traditional 'after‐the‐fact' auditing practice. Real‐time audits have been widely used in the auditing of COVID‐19 relief programmes in many countries. Whereas in the United States and many other countries, this practice became popular only in recent years, Israel's SAI in Israel has been conducting real‐time audits since the 1970s. The article surveys SAI practices in various countries regarding the timeliness of the auditing of public agencies and presents the pros and cons of real‐time audits based on an analysis of the Israeli experience. We conclude by outlining several issues that SAIs should consider before choosing to conduct a real‐time audit. [ABSTRACT FROM AUTHOR]

This study uses material weakness (MW) disclosures to explore whether auditors systematically assign greater risk to specific financial statements and account types. Auditing Standard 2201 mandates auditors adjust their levels of material weakness detection in response to the risk associated with each control being tested. Using a sample of firm years with financial misstatements, I show that auditors are most likely to detect material weaknesses in advance of misstatement discovery when they relate to the income statement, followed by the balance sheet, and to revenues and assets, relative to other income statement and balance sheet accounts. These results suggest that auditors, on average, assign the greatest level of associated control risk to the income statement, then the balance sheet, and that revenues and assets are the drivers of that assignment. [ABSTRACT FROM AUTHOR]

This study investigates the impact of two changes to the auditor's report—a separate section addressing going concern uncertainties (GCU section [GCUsec]) and information on management and auditor responsibilities—and the characteristics of the audit committee on bank directors' perceptions and decisions. In a 2 × 2 × 2 between‐subjects experimental design with 85 German bank directors, we observe that a GCUsec in the auditor's report leads to more unfavourable decisions. Contrarily, explanations of responsibilities and different characteristics of the audit committee do not significantly impact on bank directors' perceptions and decisions. We thus confirm the effectiveness of the International Auditing and Assurance Standards Board (IAASB)'s revision of the International Standard on Auditing (ISA) 570 to enhance the informational value and decision usefulness of the auditor's report. [ABSTRACT FROM AUTHOR]

Inverted metamorphic Ga0.3In0.7As photovoltaic converters with sub‐0.60 eV bandgaps grown on InP and GaAs are presented. Threading dislocation densities are 1.3 ± 0.6 × 106 and 8.9 ± 1.7 × 106 cm−2 on InP and GaAs, respectively. The devices generate open‐circuit voltages of 0.386 and 0.383 V, respectively, under irradiance producing a short‐circuit current density of ≈10 A cm−2, yielding bandgap‐voltage offsets of 0.20 and 0.21 V. Power and broadband reflectance measurements are used to estimate thermophotovoltaic (TPV) efficiency. The InP‐based cell is estimated to yield 1.09 W cm−2 at 1100 °C versus 0.92 W cm−2 for the GaAs‐based cell, with efficiencies of 16.8 versus 9.2%. The efficiencies of both devices are limited by sub‐bandgap absorption, with power weighted sub‐bandgap reflectances of 81% and 58%, respectively, the majority of which is assumed to occur in the graded buffers. The 1100 °C TPV efficiencies are estimated to increase to 24.0% and 20.7% in structures with the graded buffer removed, if previously demonstrated reflectance is achieved. These devices also have application to laser power conversion in the 2.0–2.3 µm atmospheric window. Peak laser power converter efficiencies of 36.8% and 32.5% are estimated under 2.0 µm irradiances of 1.86 and 2.81 W cm−2, respectively. [ABSTRACT FROM AUTHOR]

Recently, the doping‐less tunnel FET has gained popularity due to its lower process complexity than conventional TFETs with heavily doped source and drain regions. In this literature, we have introduced a symmetric gate Ge/GaAs heterojunction doping‐less TFET(SG HJ DL TFET) using 4.6 eV work function for both the top gate and bottom gate and an asymmetric gate Ge/GaAs heterojunction doping‐less TFET (AG HJ DL TFET) using 3.9 eV work function as top gate and 4.6 eV work function as a bottom gate. A comparative study has been performed between these two devices. The back gate misalignment engineering in the AG HJ DL TFET induces higher charge plasma near the source‐channel junction which will enhance the drain current. Due to a larger drain current, an improved ION/IOFF ratio (11.8 times), and steeper SS (37%) are achieved in optimized AG HJ DL TFET than SG HJ DL TFET. Furthermore, the Analog/Radio Frequency and linearity performance parameters have been examined, and a significant improvement is noticed in the optimized AG HJ DL TFET. The impact of different interface trap charges (ITCs) on device performances is also investigated and it is found that AG HJ DL TFET shows more immunity to ITCs than SG HJ DL TFET. Finally, the Verilog‐A‐based model has been developed for the AG HJ DL TFET to utilize its circuit‐level behavior. The optimized device‐based Common Source amplifier (CS amplifier) has been simulated in the Cadence Virtuoso tool. The AG HJ DL TFET‐based CS amplifier offers a 6.83% improvement in voltage gain over the other reported work. [ABSTRACT FROM AUTHOR]

For the first time, a novel source extension heterojunction gate‐all‐around tunnel FET (SE‐GAA‐TFET) is proposed and examined using Synopsys TCAD simulator in this manuscript. SE‐GAA‐TFET is found to exhibit improved performance in terms of various analog/RF and DC parameters. As channel/source (C/S) interface and electric field exerted by gate are perpendicular to each other, radius of channel is downscaled to enhance electric filed, without reducing area of the tunneling. Furthermore, the presence of GaSb/GaAs heterojunction at C/S interface leads to reduction in the effective band overlap, which helps a great number of mobile charges to tunnel through C/S boundary at ON‐state. The consequences of variation in different geometrical metrics are evaluated to optimize the device performance. SE‐GAA‐TFET is found to offer a current switching ratio (CSR) of ~1013 along with 32.2 mV dec−1 of average sub‐threshold swing (SSAVG). Furthermore, improvement in transconductance and parasitic capacitance boost the cut‐off frequency of SE‐GAA‐TFET up to 37 GHz. Next, both positive and negative traps are introduced at S/C interface and the study reveals that there is no much deviation in parameters of the transfer characteristics like ION, SSAVG, and IOFF of SE‐GAA‐TFET. Next, proper benchmarking is done to compare the performance of the SE‐GAA‐TFET with similar devices available in literature and it is found that proposed SE‐GAA‐TFET exhibits better DC performance due to improved electrostatic behavior. Finally, SE‐GAA‐TFET is found to offer better fall time along with full‐voltage swing when deployed in a resistive load inverter. [ABSTRACT FROM AUTHOR]

As the key component of transceiver, power amplifier (PA) plays an extremely important role in wireless communication system. In order to accurately characterize the performance variation of PA at any temperature, the temperature behavior of a gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) high gain monolithic microwave integrated circuit (MMIC) PA is modeled in this paper. In this modeling, the resilient back propagation neural network (BPNN) is utilized to do the temperature behavior modeling for this PA. The investigation shows that the minimum mean square error (MSE) of the prediction results is 4.9607 × 10−4, which implies that it is feasible to use this modeling method to characterize the temperature behavior of PA. This modeling not only theoretically overcomes the problem of slow convergence speed of BPNN, but also solves the limitation of experimental devices and time setting. It will provide a more convenient guidance for test engineers. [ABSTRACT FROM AUTHOR]

GaAs remains one of the crucial materials for solar cell applications as it boasts the world's highest efficiency single‐junction solar cells. However, their high cost limits their widespread terrestrial applications. Traditional GaAs solar cells require a complex stack of doped junctions, which can only be grown using epitaxy, which is a very costly technique. Herein, a nonepitaxial bilayer of ZnO and TiO2 as electron‐selective contact is studied. It is shown that a bilayer selective contact can achieve very high performance through interface band engineering and a reduction of the barrier for electron transfer. 21.2% efficient solar cells is achieved, with Voc of 1.04 V, Jsc of 26.13 mA cm−2, and a fill factor of 77.8%. The Voc reported in the article is comparable to the highest Voc reported for substrate‐based GaAs solar cells of 1.075 V. An experimental loss analysis shows that the device is mainly limited by series and shunt resistance and reflection losses, both of which can further be minimized by optimization of the fabrication process. The results presented will be very useful for the further development of cheaper GaAs solar cells, whereas the bilayer selective contact concept can be implemented for other kinds of solar cells. [ABSTRACT FROM AUTHOR]

The Exposure Draft for Proposed International Standard on Sustainability Assurance (ISSA) 5000 has been issued by the International Auditing and Assurance Standards Board (IAASB) because there is increasing demand by stakeholders for assurance of sustainability information. Our recommendations include: (i) a more flexible approach to ethics and quality management instead of the requirements for standards that are at least as demanding as the accounting profession's standards; (ii) more differentiation between the requirements for limited as opposed to reasonable assurance and (iii) more cautious use of the term materiality and clearer definitions of the different materiality concepts to avoid potential confusion. [ABSTRACT FROM AUTHOR]

Erbium (Er)‐doped III‐V semiconductors are promising for optoelectronic devices due to the unique intra‐4f electronic transitions of Er3+; however, the Er‐related luminescence at room temperature has always been challenging to obtain. In this work, High crystalline quality ErAs:GaAs films are grown with self‐assembled ErAs nanoparticles embedded within the GaAs matrix by molecular beam epitaxy. Rich photoluminescence spectra in a broad wavelength ranging from near‐ultraviolet to near‐infrared are observed at room temperature and confirmed to be Er‐related. A carrier‐mediated energy transfer up‐conversion mechanism is proposed, and the pump power‐dependent photoluminescence results reveal that the excited‐state absorption is governed by a single photonic process. The efficient interaction and energy transfer between the semiconductor matrix and Er3+ ions offered by this unique nanocomposite material provide a promising route to achieve novel optoelectronic devices with the potential to cover a broad wavelength range. [ABSTRACT FROM AUTHOR]

The present work analyzes the long‐term in situ comparison of Si and GaAs solar array based on two BeiDou Navigation Satellite System satellites in medium Earth orbit (MEO). From the 6 year long‐term perspective, both Si and GaAs solar arrays exhibit significant yearly periodic variations in remote sensing current and temperature due to periodic variations in the Sun–satellite distance. The practical in situ photogenerated current degradation of Si and GaAs solar arrays in MEO orbits is analyzed by the light intensity and working temperature after calibrating. The annual degradation coefficients of Si and GaAs solar arrays are calculated to be 0.986 and 0.990, respectively, which means 13.2% and 9.6% current degradation for Si and GaAs solar arrays at the end of the 10 year life MEO satellite. Also, this article examines the temperature of the MEO orbit, with the working temperature ranging from −144.7 to 56.3 °C for Si solar array and −136.9 to 60.9 °C for GaAs solar array. The present work provides a critical accurate degradation parameter for the MEO satellite's precise design and the space application of the low‐cost silicon solar cell. [ABSTRACT FROM AUTHOR]

In October 2022, the International Auditing and Assurance Standards Board (IAASB) issued Exposure Draft 500 (ED‐500). This is focused on revising and integrating the standard auditors use when evaluating audit evidence during an external audit. This study contributes to the ongoing discourse as the IAASB evaluates feedback to ED‐500 and executes its standard‐setting agenda. We review academic literature published in the past 10 years to synthesize extant knowledge specifically on the use of technology and the application of professional skepticism during audit evidence evaluation. Our review offers factors the IAASB should consider when seeking to modernize and future‐proof its standards, suggesting improvements to the proposed ED‐500. We also identify fruitful avenues for future academic research. [ABSTRACT FROM AUTHOR]

This letter presents a novel millimetre‐wave (mm‐wave) on‐chip substrate integrated waveguide (SIW) filtering crossover using 0.25 µm GaAs pHEMT technology. The design methodology of the proposed crossover is thoroughly illustrated. The proposed filtering crossover employs a dual‐mode cavity with TE102 and TE201 degenerate mode resonances at the intersection, leveraging the degenerate modes for in‐band resonance and inter‐channel isolation. Additionally, four TE101 mode resonant half‐mode SIW cavities are coupled around the dual‐mode cavity to achieve two third‐order bandpass response channels and reduce the overall size. A prototype is designed, analysed, and fabricated to validate the proposed approach, with measured results showing good agreement with simulations. The presented on‐chip SIW filtering crossover offers promising potential for mm‐wave applications, demonstrating the effectiveness of the design methodology and GaAs pHEMT technology integration. [ABSTRACT FROM AUTHOR]

The authors demonstrate a large‐area vertical‐cavity surface‐emitting laser (VCSEL) 25 × 35 array on a p‐type GaAs substrate with an emission wavelength of ∼940 nm and optical output power > 1 W, using an inverted junction (n‐up) epitaxial structure for emerging sensing applications. The electrical characteristic (series resistance) of the inverted n–p VCSELs is better than that of standard p–n VCSELs, but optical characteristics (the threshold current density and slope efficiency) are worse possibly due to crystalline defects originating from the p‐type substrate whose effect could be avoided in small‐area VCSELs. Other inverted junction structures on an n‐type substrate are needed for further development. [ABSTRACT FROM AUTHOR]

A 24%‐efficient single‐junction GaAs solar cell grown directly on a faceted, spalled (100) GaAs substrate after in situ planarization growth by hydride vapor phase epitaxy (HVPE) is achieved. Controlled spalling, a promising low‐cost substrate reuse technique, produces large facets in (100)‐oriented GaAs substrates due to the orientation of the fracture planes used for lift‐off. Planarization by HVPE offers a path toward direct use of these spalled substrates without costly polishing steps. Here, the growth rate anisotropy enabling planarization arising from diffusion and differences in the adsorption of growth species on {n11}B‐type facets relative to (100) is determined. Consecutive planarization and device growth that results in a solar cell with a minimal performance difference relative to a control cell grown on an epitaxy‐ready substrate are demonstrated. These results show that controlled spalling coupled with HVPE planarization is a viable pathway for lowering the cost of III‐V photovoltaics. [ABSTRACT FROM AUTHOR]

Functional unit and organization (FUO) paradigm starts with functional units and assembles these functional units into specific organizations to optimize material performance. An advantage of FUO paradigm is interpretation of physical essence of traditional structure–performance relationships. Experimental achievements based on FUO paradigm abound in recent years, demanding theoretical explanations for further quantitative material design. Following FUO paradigm, here a three‐step model (bond‐region‐structure) of nanotwin (NT) unit and orientation organization to optimize mechanical performance is established. First, anisotropic elasticities of representative bonds and assembled regional elastic constants are evaluated. Second, yield conditions of different regions, which are summarized as critical resolved shear stress (CRSS) criteria of NT structure, are quantified. Third, anisotropic yield strengths of NT structure from the regional elastic constants and CRSS criteria are derived. This FUO‐based model is implemented into InSb, GaAs, and ZnS, predicted elastic constants and yield strengths are validated with molecular dynamics (MD) simulations. The method is more efficient than MD with comparable accuracy, and is also flexible to combine with density function theory and experiment. This demonstration sets foundation of NT unit and orientation organization design for achieving optimum mechanical performance. [ABSTRACT FROM AUTHOR]

A front‐end MMIC working at 37–43.5 GHz for 5G high‐performance channel emulator is presented in this paper. The chip is fabricated in a 0.1‐μm commercial GaAs pHEMT process and integrated with a passive star mixer and a local oscillator (LO) chain, which is composed of a frequency tripler, a bandpass filter, a power amplifier, and an LO filter. The 10.5 GHz intermediate frequency (IF) signal is upconverted with the high frequency LO signal of 48–54 GHz through a passive double‐balanced star mixer, which can output 37–43.5 GHz radiofrequency signal. The high frequency LO can avoid the increase of bit error rate caused by the frequency band of input signal covering IF frequency. The conversion gain of −11.2 to −9.7 dB, the OP1‐dB of −0.26 to 1.7 dBm are achieved and the front‐end chip occupies an area of 2.78 × 0.9 mm2. [ABSTRACT FROM AUTHOR]

III–V solar cells are mainly grown on GaAs or Ge substrate, which significantly contributes to the final cost and affects the sustainable use of these rare materials. A so‐called PEELER process is developed, in which a porosification technique is used to create a weak layer between a Ge substrate and the epitaxial layers. This method enables the separation of the grown layers, allowing for the subsequent reuse of germanium and a reduction in the environmental and economic cost of optoelectronic devices. Technology validation using the device performance is important to assess the technology interest. For this purpose, the performance of 22 nondetached single‐junction GaAs photovoltaic cells grown and manufactured on porosified 100 mm Ge wafer without antireflection coating is fabricated and compared. All the cells exhibit comparable performance to state‐of‐the‐art GaAs solar cells (grown or Ge or GaAs) with high efficiency (21.8% ± 0.78%) and thereby demonstrate the viability of growing high‐performance optoelectronic devices on detachable Ge films. [ABSTRACT FROM AUTHOR]

Increasing the disclosure of key audit matters (KAMs) has been an important change in audit reports in recent years. After the implementation of this policy, what changes have taken place in the behaviour of auditors after the implementation of this policy? What impact has it had on the audit report? A series of problems deserve systematic analysis and empirical testing. This paper examines the relationship between the communication of KAMs and earnings management. We examined quasi‐natural experimental data shaped by new auditing standards issued by the Ministry of Finance of China on 23 December 2016. The new auditing standards have been implemented in phases for the listed companies. We find that (1) communicating KAMs in audit reports restrains the auditor's motivational reasoning behaviour by triggering rationality constraints and improves the auditor's professional scepticism, thus improving audit quality and significantly reducing the company's accrued earnings management level. (2) The influence of communicating KAMs on earnings management is more significant for sampled firms with high external financing dependence and low marketization, revealing its supplementary role in the existing corporate governance mechanism. The findings of this paper enrich existing research on KAMs and supplement important empirical evidence from the Chinese market for assessing the effects of audit reporting reforms worldwide. [ABSTRACT FROM AUTHOR]

This study aims to extend research on the effect of PCAOB inspections on audit firm behavior by examining generally accepted auditing standards (GAAS) and generally accepted accounting principles (GAAP) type PCAOB inspection deficiencies, separately, to reveal the differential effects on audit fees in subsequent years. We empirically examine the audit fees of 98,393 client firm‐year observations for auditors who received a PCAOB inspection report during 2004–2021 via multivariate regression analyses. We find that GAAS (GAAP) deficiencies are associated with higher (lower) audit fees in the years following the reported deficiency. Our results suggest that the PCAOB inspection process modifies audit firm behavior when GAAS deficiencies are reported leading to the firm charging higher audit fees to defray the costs of addressing the deficiencies, but due to the severity of GAAP deficiencies that are identified, audit firms are willing to negotiate lower fees to retain the client. Our results are primarily driven by annually inspected audit firms. These results suggest that auditors respond to GAAS and GAAP PCAOB inspection deficiencies differently. The results of our study are useful to regulators and policymakers, such as the SEC and the PCAOB, in understanding how auditors respond to PCAOB inspection deficiencies and their due diligence to correct those deficiencies. PCAOB inspections are intended to evaluate compliance with accounting and auditing standards to improve audit quality and our study helps to extend the research to date which has not yet clearly demonstrated whether or not this has been accomplished. [ABSTRACT FROM AUTHOR]