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We propose and design a novel homogeneous nanorod-assisted multi-core photonic crystal fiber (NA-PCF), and it utilizes the flexibility of photonic crystal fiber (PCF) for air-hole design, NA-PCF applied to multi-core fiber (MCF) communication system. High refractive index nanorods are introduced in the center of the seven cores which are further surrounded by a periodical arrangement of air-holes. The air-holes and the nanorods work together to greatly suppress the crosstalk (XT) between the cores. By comprehensively balancing the influence of various parameters on XT, single-mode cutoff wavelength (λcc) and the effective mode field area (Aeff), simulation results show that the NA-PCF has a Aeff of about 70.26 μm2, XT of about −50.58 dB/km, relative core multiplicity factor (RCMF) of 4.7 and λcc of 1530 nm. This designed structure targets applications in large-capacity long-distance MCF communication.

Modern transportation systems, such as aircraft, are increasingly replacing metal body parts for composite materials, such as carbon-fiber reinforced plastics. Despite the multiple advantages in terms of weight, size, and fuel consumption, this trend is posing a challenge for protection of cables against electromagnetic interference. Early risk assessment and optimization of cable design in modern aircraft require reliable methods that can quickly and accurately estimate crosstalk behavior in the presence of lossy ground planes. This article presents two novel methods to incorporate such lossy ground planes into the crosstalk modeling of cable bundles. The first method considers the ground plane as a discrete collection of cylindrical conductors. In the second method a ground impedance matrix is derived for lossy ground planes with a finite thickness. Results of both methods are compared to full-wave simulations and measurements, yielding excellent results in terms of accuracy and computation times. The discretized ground plane method is also applied to the case of wire pairs that are enclosed by two ground planes, both aluminum and carbon–fiber reinforced plastic, as a first step towards investigation of wiring that is embedded in thermoplastic material. Once more simulations and measurements are in good agreement.

Hollow dielectric waveguides (HDWs) are renowned for their extremely low-loss transmission among all dielectric -based solutions. Highly-integrated multilane HDWs are expected to be applied for increasing demand on high-throughput communication. Unfortunately, severe crosstalk and loosely confined electromagnetic field have been a critical issue for a long time. In this article, we demonstrate a novel 1-D photonic crystal fence. Photonic particles represent a series of guard lining up beside the waveguides. Over 30-dB crosstalk reduction can be realized for closely placed HDWs. This proposed method, without altering the original structure of HDWs, offers high degrees of freedom for the HDW design. The experimental results show good field confinement in the mm-wave range, but not limit to it. This all-dielectric -based solution implies its opportunity for subterahertz to optical frequency application. Moreover, photonic crystal fence with only 1-D arrangement makes this concept feasible for both tubular HDWs and other planar integrated dielectric -based waveguides on board. This technique takes a key step for highly integrated multilane HDWs in the near future.

Because SiC MOSFET-based zero-voltage switching (ZVS) power converter circuits provide high-speed switching, high power density and high efficiency can be achieved. However, an undesired negative spike is formed at the gate-source voltage owing to the crosstalk phenomenon in leg structures, such as half-bridge switch configurations, during high-speed switching. Additionally, ringing voltage occurs owing to resonance between the snubber capacitor and the common source inductance of the SiC MOSFET. Because SiC MOSFETs have a lower gate voltage rating than conventional Si devices, it is essential to reduce the negative spike and ringing voltages to ensure reliability. In this paper, the gate driver circuit is proposed for reducing the negative spike and ringing voltages of the gate-source in ZVS circuits. Because the proposed gate driver circuit provides an effective impedance path for each section through an active switch, a stable driving voltage range of the gate-source can be achieved. To verify the proposed gate driver circuit, an accurate simulation model of the 3-pin SiC MOSFET package is proposed, and the validity of the proposed model is verified through comparison of the simulated waveforms with experimental waveforms. The performance of the proposed gate driver circuit is verified through PSpice simulation.

The potential role of multicore fibers (MCFs) in submarine cable systems is investigated in the context of electrical power limitations and physical fiber count limitations. We compare the maximum cable capacity theoretically possible for cables using MCFs with 2, 3, and 4 cores to that of cables built with conventional single-core fibers. The comparisons are made based on ideal Shannon-limited capacity, systems with constant output power amplifiers, and individual amplification of MCF cores using fan-in/fan-out devices. MCFs are assumed to have nominally uncoupled cores for which crosstalk between cores is a system impairment. We examine the relative cost/bit of systems built with MCFs and single-core fibers when designed for maximum capacity, and when designed for minimum cost/bit operation. The relative capacity of a cable with MCFs depends strongly on the number of fibers able to be physically accommodated and is greatest when the fiber count number is relatively small. We find only small differences in the relative capacities of MCFs with 2-4 cores and that any advantage over single-core fiber systems can be eroded with minimum signal-to-noise ratio (SNR) requirements above the theoretical level near 0 dB that maximizes cable capacity. The cost/bit of MCF cable systems is determined to be higher than that of single-core fiber systems when maximum cable capacity is the design goal, according to the cost model employed and the specific system and fiber parameters assumed here. Different results may be obtained with cost model refinements and different parameters.

In the paper, the model of micron-level crosstalk interconnections was constructed based on FR4 substrate. By changing the input variables of the length and the spacing, this prediction model could provide useful information for Crosstalk intensity. With the increase of the length of the interconnect, the crosstalk intensity of the proximal end and the distal end increased. When the interconnect spacing increased, the trend of crosstalk was not changed, but the intensity decreased gradually. Which provided an experimental reference for future methods of reducing crosstalk from the perspective of physical structure.

Polymers are widely used as insulators in electronic devices. Low dielectric constant polymers are desirable since this lowers the potential for unintentional crosstalk and inductive coupling betwe...

Patterning multiple images within a single element without crosstalk can significantly increase the information capacity and security, but it is challenging to enable the response capability in each image. Now, the patterning of crosstalk-free yet cooperative-thermoresponse images (holographic and fluorescent images) is successfully achieved by designing a liquid crystal (LC)/AIEgen system with a unique synergy. The AIEgen's fluorescence intensity is controlled by the LC, while the LC's phase transition is in turn promoted by the AIEgen. The fluorescent image contrast is significantly boosted by efficient energy transfer (ΦET : 96 %) from the LC to the AIEgen. The AIEgen's photocyclization for fluorescent patterning occurs in a zero-order kinetic manner and can be completed within several minutes when assisted by the LC. The photocyclization conversion is quantitatively dependent on the aggregation size: α∼exp(-d), and able to reach as high as 98 %.

A comprehensive analysis is carried out herein on the impact of the interconnect geometry with nanoscale dimensions on the crosstalk-induced gate oxide reliability in coupled multilayer graphene nanoribbon (MLGNR) interconnects. Simplified circuit models are used to capture the temperature-dependent phonon scattering at temperatures from 300 to 500 K. Three different cases (case-1, case-2, and case-3) of coupled interconnects with fixed sum of width and spacing (interconnect pitch) but varying width/spacing (w/s) ratio are analyzed, revealing that the coupled interconnect geometry controls the impedance parameters. Functional crosstalk analysis shows that the highest positive noise peak of the victim output over the temperature range from 300 to 500 K is obtained in case-3, where the w/s ratio is maximum. On the other hand, the reverse is true for the time duration of the noise pulse at the far end of the victim line in case-2. Analysis of the dynamic crosstalk then reveals that an average percentage delay of approximately 13.45% is obtained in case-3 with respect to (w.r.t.) case-1, while a marginal difference is found in case-2. In comparison with temperature-independent circuit models, the results obtained using the temperature-dependent circuit models of the coupled MLGNR interconnects show an average relative improvement in the time duration of the noise pulse at the victim output by approximately 39%, 35.6%, and 46.6% in case-1, case-2 and case-3, respectively, for the different lengths. The gate oxide reliability in terms of the average failure rate (AFR) for coupled MLGNR interconnects with different widths and lengths is further investigated. The results show an infinitesimal increment of the AFR with the increase in the width and length of the MLGNR interconnects. Moreover, they reveal that the interconnect geometry in case-3 is more prone to gate oxide failure compared with the other cases.

This article proposes a novel differential through-silicon via (D-TSV) structure, which is filled with vertically aligned carbon nanotube (VACNT) array. Two metal pads are deposited on the sides of the surface of the proposed D-TSV to form differential signal transmission paths. The equivalent circuit model is established for the proposed D-TSV, with the frequency-dependent impedance extracted using partial-element equivalent-circuit (PEEC) method. By virtue of the equivalent circuit model, the electrical performance of the proposed D-TSV is investigated, with some design guidance presented.

A silicon nitride waveguide crossing based on multimode-interference is designed and fabricated. By optimizing the structure parameters with finite difference time domain method, 0.3 dB insertion loss and −75 dB crosstalk at 1550 nm are obtained. Then the designed waveguide crossing is fabricated based on the double strip silicon nitride waveguide. The measured results show the insertion loss and crosstalk are about 0.6 dB and below −42 dB, respectively, in the wavelength range of 1520 nm ∼ 1640 nm with low polarization dependence. The waveguide crossing could be a key building block for the silicon nitride waveguide platform.

We realized a four-core fiber with 125 μm-cladding and four-holes using a novel fabrication technique, namely the over-cladding bundled rods (OBR) method. Four air holes were successfully introduced by using the OBR method without the need for a drilling process, and this enabled a 10 dB/km improvement in the crosstalk characteristic. As a result, we realized four-core fibers with a 125 μm cladding diameter and operating in both the single mode and 2 linear polarized (LP) modes in the C + L band were realized while maintaining an inter-core crosstalk of less than −30 dB/100 km. The OBR method is a promising technique for effectively realizing a multi-core fiber with ultra-low crosstalk and a high spatial density.

We developed a low-mode-crosstalk coupler using silica planar lightwave circuit (PLC) technology. The coupler has two mode conversion stages. One is a mode converter for converting the fundamental mode to the second-order mode, and the other is for converting the second-order mode to the first-order mode, which is the target mode. Isolation between fundamental mode and first-order mode can be enhanced by using indirect conversion with the second-order mode instead of direct conversion. In the fabricated coupler, the mode crosstalk between the fundamental mode and first-order mode was under -30 dB, and the conversion ratio was -0.8 dB at the wavelength of 1050 nm. The coupler can be used for sensitive 1 μ m-band mode-detection optical time-domain reflectometry.

Metal wires and through silicon vias (TSVs) are frequently performance bottlenecks of 3D ICs due to their high capacitive crosstalk which can be reduced using coding techniques. In this work we show that existing TSV crosstalk avoidance codes (CACs) are impractical for real applications due to the edge effects in TSV bundles. Additionally, these 3D CACs do not reduce the metal wire crosstalk and dramatically increase the power consumption of 2D and 3D interconnects. This work presents a 3D CAC which overcomes previous limitations. The method is based on an intelligent fixed mapping of the bits of existing 2D CACs onto rectangular or hexagonal TSV arrangements. Simulation results, obtained by circuit simulations in combination with an electromagnetic field solver, show that existing 3D CACs only reduce the TSV crosstalk by a maximum of 9.4%, provide no optimization of the metal wire crosstalk and induce an increase in the interconnect power consumption by about 50%. In contrast, the presented technique requires less hardware and reduces the maximum crosstalk of modern TSV and metal wire buses by 37.8% and 47.6%, respectively, while leaving their power consumption almost unaffected. Alternatively, our technique can reduce the TSV and metal wire crosstalk peaks by 20.3% and 47.7%, respectively, while additionally providing a reduction in the TSV and metal wire power consumption by 5.3% and 21.9%, respectively.

This paper presents temperature-dependent circuit modeling and performance analyses of single as well as capacitively coupled interconnects of a mixed CNT bundle (MCB) with consideration of the tunneling effect at temperatures from 300 to 500 K at the 14-nm technology node. Four possible MCB structures, viz. MCB-1, MCB-2, MCB-3, and MCB-4, are considered, and their results are compared with those for a copper-based interconnect at the same technology node. For the single line architecture, as the temperature is increased from 300 to 500 K, MCB-4 exhibits a shorter propagation delay in comparison with the other MCBs (1–3) and copper. The results of the frequency spectrum analysis reveal that MCB-4 exhibits a 17.70% wider bandwidth than its copper counterpart. Also, the bandwidth of MCB-4 decreases with increasing temperature, indicating greater signal loss at higher temperatures. For the coupled line architecture, considering different switching conditions of the aggressor and victim lines, MCB-4 exhibits a shorter average dynamic crosstalk-induced delay compared with the other MCBs (1–3) or copper. In comparison with the odd mode of switching, MCB-4 exhibits a 36.45% shorter crosstalk-induced delay with the even mode of switching when the temperature is varied from 300 to 500 K. Similarly, the functional crosstalk noise levels in terms of the overshoot, undershoot, rise glitch, and fall glitch are also found to be significantly lower for MCB-4 compared with the other MCBs (1–3) or copper. The results of the simulations further reveal that MCB-4 exhibits frequency noise components with 70.66% lower amplitude compared with copper, which means that MCB-4 filters more noise components than copper. Furthermore, the amplitude of the frequency noise components increases with rise in temperature.

A new kind of gold-coated hexagonal photonic crystal fiber polarization filter is designed in this paper. The filtering properties can be adjusted through varying the structural parameters. With the 25.60 nm gold film thickness, the losses of the respective modes of Y and X-polarized core mode at 1550 nm are 1024.84 and 0.12 dB/cm with the loss ratio of 8540.33 between two polarizations. However, the losses of Y and X-polarized core mode at 1310 nm are 682.14 and 0.03 dB/cm, and the loss ratio is 22,738 with the gold film thickness of 55.30 nm. That indicates that the proposed filter has a higher loss ratio. Moreover, the crosstalk value with the fiber length of 200 μm at 1550 and 1310 nm are 178.01 and 118.49 dB, respectively. The bandwidths with crosstalk value greater than 20 dB are 640 and 180 nm. The designed polarization filter represents good filtering characteristics and allows great fabrication tolerances. Therefore, the designed hexagonal filter can be well applied in the domain of optical fiber communication.

In this paper, the properties of crosstalk on SiC planar MOSFET, SiC symmetrical double-trench MOSFET and SiC asymmetrical double-trench MOSFET is investigated on a half-bridge topology, to enable analysis of the impact of temperature, drain-source transition speed and gate resistance on the severity of the shoot-through current and induced gate voltage. The experimental measurements, performed on a wide range of temperatures and switching rates, show that the two selected symmetrical and asymmetrical double-trench MOSFETs exhibit higher induced gate voltage during crosstalk with the same external gate resistance compared with the planar SiC MOSFET, yielding a higher shoot-through current. Therefore, in continuous initiation of intentional crosstalk, the two double-trench MOSFETs experience more temperature rise, especially for symmetrical one which leads the device to verge of failure within minutes while the temperature rise in other two devices is significantly lower. The different trends of shoot-through current with temperature on DUTs reveals that they are dominated by different mechanisms, i.e., influenced by threshold voltage and inversion layer carriers' mobility. A model is developed for prediction of shoot-through current during crosstalk which is validated for the 3 device structures. The comparison of the modelled results with the measurement proves its capability to predict the crosstalk behaviour.

International audience; To improve the problem of narrow bandwidth and large crosstalk in high-frequency PMUT array, a PMUT device with a damping backing structure (B-PMUT) is proposed and realized. The device is a two-dimensional array of 8×16 elements with an element pitch of 75 µm. The results show that the bandwidth of the device with backing is more than doubled (63%) to that of without backing. The crosstalk level between two neighboring elements decreased from −13.4 dB to −17 dB.

This Letter presents a novel RF ground lead structure for surface-mount-type optical modules that enables RF crosstalk reduction and bandwidth enhancements. Conventional RF lead-pins of a surface-mount-type optical module have a bent shape that affects on RF ground stability and RF crosstalk between channels. The authors introduced an enhanced ground lead with an optimised shape for RF ground scheme enhancement. They prepared two types of high-bandwidth coherent driver modulator packages for demonstrating RF performance difference, one with the conventional bent ground lead and the other with the optimum-shaped ground lead. The measured results of the package with the enhanced ground lead successfully exhibited adjacent far-end crosstalk reduction of about 5 dB at 50 GHz, and the crosstalk of −30 dB or less up to 58 GHz was confirmed. Moreover, they obtained the improvement in the insertion loss of 1 dB at 54 GHz and the 3-dB electrical bandwidth enhancement of 2 GHz. These RF performances are sufficient for a high-bandwidth coherent driver modulator package that allows 96-GBd class operations.

This paper deals with the research proposal and evaluation of Strongly coupled MCF which is studied in propagation mode retaining capability as regular multi-mode fiber has an issue of mode crosstalk. As a result, mode retention characteristics of 5 dB at 80 mm bending radius has been confirmed successfully.

Structural hybridization and size miniaturization of integrated photonic devices are among the hotspots of photonics research field. The crosstalk between densely arranged subwavelength-width optical waveguides such as optical microfibers has become an important issue. Here we investigate a common case of crosstalk in two intersecting subwavelength-diameter optical microfibers at 1550-nm wavelength by numerical simulations and experiments, and obtain the dependence of coupling efficiency and crosstalk on modal polarizations, intersection angle, fiber diameter and separation of the two fibers, respectively. The simulation results show that, the crosstalk decreases with increasing intersection angle and separation between the two microfibers. Especially, for single-mode microfibers, the crosstalk is lower than 1% (i.e., better than -20 dB) when the intersection angle is larger than 60°, and can be minimized to less than 0.05% (i.e., better than -33 dB) for perpendicular intersection (i.e., intersection angle of 90°). However, the dependence of crosstalk on fiber diameter is not monotonous, typically, from the single-mode cutoff diameter, the crosstalk increases with decreasing diameter until reaching a maximum, and decreasing afterward. To verify the simulation, we have experimentally measured the angle-dependent crosstalk between contacting microfibers with typical diameters. With increasing intersection angle, the crosstalk drastically decreases to a negligible value (less than -41 dB for vertically intersecting microfibers), which is consistent with the simulation results. Our results offer a valuable reference or guideline for designing compact optical interconnection and integration with optical microfibers or other subwavelength-width waveguides alike.

For terahertz (THz) integrated systems, an intersection between waveguides is inevitable and is often accompanied by considerable crosstalk and loss. Here, we propose and experimentally demonstrate a novel type of crossing with a footprint less than 0.2 × 0.2 mm2 for THz surface plasmon polariton waveguiding. With an optimized crossover structure, the measured loss of the intersection is as low as 0.89 dB/crossing, and the crosstalk is less than −19.06 dB/crossing at 0.55 THz. The proposed crossing structure is compact and has low loss and crosstalk within a broad band, which will pave the way for a wide range of new applications for THz integrated systems.

Ring resonators have always been referred to as a highly flexible structure for designing optical devices. In this paper, we have designed and evaluated two 8-channel optical demultiplexers...

A novel heterogeneous double period array multicore fiber (DPAMCF) is proposed, in which the spacing between two adjacent cores is approximately equal and the core sizes change periodically. The modes in the DPAMCF form two supermode groups, which can be attributed to double period distribution of heterogeneous cores. Two supermode groups are phase mismatched and the coupling crosstalk between them is suppressed. Fiber Bragg gratings (FBGs) are successfully inscribed in the DPAMCF and the responses of each grating to the axial strain and temperature are measured. The proposed DPAMCF offers a platform to integrate a series of FBG units with two sets of different Bragg wavelengths into a plane at the same longitudinal position.

We demonstrate highly efficient couplers in a two-dimensional grating configuration for a vertical fiber-coupling fabricated in the silicon-on-insulator platform. A combination of sub-wavelength reflectors and blazed gratings enables both high coupling efficiency and vertical grating coupling. We experimentally achieve coupling efficiencies of -2.6 dB at 1544 nm and -3.4 dB at 1536 nm for x- and y-polarized LP01 modes, respectively. The experimental results are in good agreement with the simulated -2.4 dB coupling efficiency for both polarizations at a wavelength of 1550 nm. Simulated and measured crosstalk between two polarizations were -19 dB and, IEEE Photonics Journal, 11 (4), ISSN:1943-0655

We present a silicon nitride (SixNy) arrayed waveguide grating (AWG). Crosstalk in this AWG was reduced by decreasing the phase error in a multimode arrayed waveguide (WG) at center wavelength of 838 nm. 8-channel SixNy AWGs using arrayed WGs with double-etched inverse-tapered WG structure and cross-sectional area of $1.5 \times 1.5\,\,\mu \text{m}^{{2}}$ were fabricated. The AWG exhibited less than −29.6-dB crosstalk with 0.43-dB insertion loss for transverse electric (TE) polarization.

In this work, thickness of AsF5 intercalation doped, Multilayer Graphene Nanoribbon (MLGNR) interconnects is optimized by minimizing various performance and power metrics (i.e. crosstalk-induced si...

We review recent advances in magnetic sensors for DC/AC current transducers, especially novel AMR sensors and integrated fluxgates, and we make critical comparison of their properties. Most contactless electric current transducers use magnetic cores to concentrate the flux generated by the measured current and to shield the sensor against external magnetic fields. In order to achieve this, the magnetic core should be massive. We present coreless current transducers which are lightweight, linear and free of hysteresis and remanence. We also show how to suppress their weak point: crosstalk from external currents and magnetic fields.

A new optical fiber sensor for vibration measurement has been proposed and demonstrated. This paper realizes vibration sensing based on the macrobending loss in a standard single-mode fiber loop. The experiments shows the suggested sensor enable us to measure multi-frequency vibrations with the resolution as high as 0.04 Hz. The crosstalk between temperature and vibration can be ignored because the macrobending loss is insensitive to the ambient temperature.

This study presents an efficient geometry for active shielding of multiwalled carbon nanotube (MWCNT) bundle interconnects which cancels the crosstalk-induced functional failures in ternary logic. In this geometry, MWCNT bundles are used innovatively as shields on both sides of the signal transmission line to reduce the crosstalk effects while maintaining the minimum interconnect pitch. Simulations are performed using HSPICE for intermediate and global interconnects in ternary logic at 14-nm node. The results indicate that the crosstalk-induced functional failure in ternary logic is omitted by using the proposed structure. Moreover, according to the results, our proposed geometry reduces the crosstalk noise peak as compared to the widened MWCNT bundles, distanced MWCNT bundles and Cu interconnects on average by 41%, 44%, and 61% for the intermediate interconnects and 61%, 46%, and 74% for the global interconnects, respectively, without any considerable power consumption penalties.

GaN based Photonic Integrated Circuits (PICs) have now become a global contender for their wide range of applications owing their physical characteristics. The GaN material system acts as a promising platform; compatible with silicon and sapphire substrates. Both the carrier transport and carrier removal techniques are vital to develop the efficient platform for the integration of photonic circuits. We demonstrate the carrier removal mechanism in silicon (Si) doped GaN (0001) epitaxially grown on c-plane sapphire wafer using ion engineering of the devices. Ion-engineered regions within the active layers of the device are modelled, fabricated and characterized to assess the isolation created. Helium and Carbon ions with pre-designed doses and energies are used to irradiate the device structures. We have modelled and fabricated ion-engineered regions within the active layers and studied the carrier transport properties on said regions to isolate that particular part with either of active photonic components placed at the common platform. After ion irradiation, detailed analysis in terms of electric field dependent current characteristics, sheet resistance, carrier mobilities, activation energies, dark and photo currents under zero (ground) and multiple biases are examined to see the extent of charge leakage and to map the charge behavior under nominal operation. Device characteristics under wide regime of annealing temperatures ranging from 300°C to 1000°C are mapped to evaluate the thermal stability of implant driven isolated regions. Activation energies of implanted and parent regions has also been studied. The dark and photon driven electric currents at ground and under biased have been measured to investigate the photo-induced transport phenomenon.

Optical crosstalk is one of major problems limiting the performance of focal plane arrays based on single photon avalanche diodes (SPADs). In this work, for the first time the crosstalk characteristics of a 4H-SiC SPAD linear array are studied, which is based on a real-time dual channel data acquisition method. It is found that SiC SPAD array exhibits similar crosstalk probability compared with those of InGaAs-based SPAD arrays, which can be effectively reduced by trench isolation between adjacent pixels or by lowering overbias. The average time required for forming a crosstalk event is determined between 7 and 10 ns. As a result, active time-gated operation scheme can be applied for reducing crosstalk.

In this paper, a novel through-silicon via (TSV) structure, named partial coaxial TSV (PC-TSV), is proposed to suppress TSV-induced substrate noise. In this structure, the via is surrounded by a benzocyclobutene (BCB) layer, and a grounded metal ring placed at one end. The BCB layer can effectively reduce the leakage of the signal to the substrate, and the metal ring provides a low impedance path for the substrate noise. An equivalent RLGC model of this structure is also established, and it is verified by simulated result from CST. Then, the performance of PC-TSV is compared with that of the traditional TSV, TSV with p+ layer, and TSV with p+ guard ring. Analysis results in frequency domain indicate PC-TSV has a larger $\vert \text{S}_{21}\vert $ and less near-end crosstalk than other three structures. Additionally, analysis results in time domain show that the substrate voltage noise of this structure is obviously reduced compared with the TSV with p+ layer and TSV with p+ guard ring. Also, a feasible process flow for this structure is given and it is simpler than that for traditional coaxial TSV.

Microstrip signal lines covered with a dielectric layer are used to reduce far-end crosstalk (FEXT) noise from adjacent lines. When minimizing FEXT noise, the permittivity of the dielectric layer should be higher than that of the substrate. When the permittivity is close to that of the substrate, the thickness of the covering dielectric layer is much larger than that of the substrate. We here present a novel means of reducing FEXT noise in microstrip lines covered with a dielectric layer using a rectangular (R)-shaped groove. When an R-shaped groove is created in the covering dielectric layer or substrate of the microstrip lines, FEXT noise is suppressed in the absence of the above conditions. To analyze the underlying mechanism, we studied the circuit parameters and electric field distribution in the microstrip lines. To confirm the improvements afforded by our methods, we compared simulated and measured data of our new structures to those of other structures.

We report, for the first time, mixed CNT bundle (MCB) as prospective interconnect in the sub-threshold regime. MCBs with spatial and random distribution of single- and multi-walled CNTs of non-identical diameters are proposed. An analytic model to compute sub-threshold crosstalk delay in coupled MCB interconnects is introduced. Using the proposed model, the impact of interconnect length on the delay performance and transfer gain for coupled MCB interconnects is studied. It is observed that sub-threshold MCB interconnects demonstrate improved crosstalk delay and higher cutoff frequency in comparison to the MWCNT and copper counterparts. The proposed model efficiently computes the performance of sub-threshold MCB interconnect system with less than 3% average error.

A time-multiplexed stereoscopic display with a wide color gamut is fabricated and introduced in this paper. It comprises a scanning backlight unit (SBLU), a 120Hz liquid crystal display (LCD) panel and a pair of LCD shutter glasses equipped with two switching lens (Manufactured by NVIDIA, Model: 3D VISION 2). We use sectional light guide plates to compress the light angle. We use blue LEDs (Domain wavelength: 450nm) to replace the traditional phosphor white LEDs used in the backlight. The blue LEDs are fixed on the edges of the sectional light guide plates, and the quantum dot-polymer (QDP) film is placed on the surface of sectional plates. The SBLU and auxiliary glasses could work together with the LCD panel. All of these components can be controlled by the vertical synchronization signal transmitted from the graphics card. The color gamut of our prototype is improved. According to ITU-R Recommendation BT.2020 (Rec.2020), the color gamut is widely extended to 77.61%. The display's ability to express color has been improved by using quantum dot (QD) material. The display brightness through the switching lens is about 120 nit. The crosstalk decreases to about 0.9%.

The downscaling of commercial one-transistor–one capacitor ferroelectric memory cells is limited by the available signal window for the use of a charge integration readout technique. However, the erasable conducting charged walls that occur in insulating ferroelectrics can be used to read the bipolar domain states. Both out-of-plane and in-plane cell configurations are compared for the next sub-10-nm integration of ferroelectric domain wall memories with high reliability. It is highlighted that a nonvolatile read strategy of domain information within mesa-like cells under the application of a strong in-plane read field can enable a massive crossbar connection to reduce mobile charge accumulation at the walls and crosstalk currents from neighboring cells. The memory has extended application in analog data processing and neural networks.

The state of mode coupling in step-index plastic-clad silica fibers is investigated in this article by numerical solving of the time-independent power flow equation. The coupling length Lc at which the equilibrium mode distribution is achieved and the length (zs) of the fiber required for achieving the steady-state mode distribution are obtained. It was found that the plastic clad silica fiber investigated in this work showed a much weaker mode coupling than the plastic-clad silica fibers investigated in earlier works. We have also shown that mode coupling significantly limits the fiber length at which the space division multiplexing (SDM) can be realized with a minimal crosstalk between the neighbor optical channels.

We demonstrate continuous tuning of a second-order silicon microring filter over the full 7.8-nm FSR of the resonators using the thermo-optic effect. Strongly correlated linear relationships between the heater powers and the filter center wavelength were obtained even in the presence of thermal crosstalks in the resonant frequencies and coupling coefficients, which allowed the filter to be tuned to any arbitrary wavelength with an accuracy of ±27 pm without the need for further optimization. We also demonstrate the use of integrated on-chip thermistors for precise tracking of the local temperatures of the microring resonators, thereby providing an indirect mechanism for monitoring the center wavelength and spectral characteristics of the filter.

著者人数: 11名, Accepted: 2018-06-15, 資料番号: SA1180190000

Ge-on-Si low-loss waveguides and 7 $\times$ 8 arrayed waveguide gratings (AWGs) are presented for operation near 4.7 $\mu$ m wavelength. Propagation loss in the range of 3 dB/cm for fully etched waveguides and 1 dB/cm for shallow-etched waveguides is reported. 200 GHz AWGs in a 7 $\times$ 8 configuration with various waveguide aperture widths and etch depths are designed and characterized. For fully etched AWGs, the insertion loss values as low as $-$ 2.34 and 3 dB mean cross talk of $-$ 29.63 dB are achieved. The shallow-etched AWG has an insertion loss of $-$ 1.52 dB and crosstalk of $-$ 28 dB.

A novel waveguide crossing with low crosstalk and crossing loss was proposed and prototyped on the Si platform. The design consists a pair of tapered Si waveguides instead of a single waveguide at the crossing point, producing a mismatch of the mode fields between the input waveguide and crossing waveguide. The tapered Si waveguides with SiN x outer cores demonstrate extremely low-loss waveguide crossing. An optical switch is prototyped by the crossing with a ring resonator, demonstrating a low-crossing loss and crosstalk, a high extinction ratio, and yet a small footprint.

In this paper, we theoretically propose an ultra-compact low crosstalk photonic crystal dual-channel sensor (DCS) for multiplexing dual-parameter sensing. To begin with, a photonic crystal (PhC) elliptical holes multimode nanobeam cavity (EMNC) is designed. By applying three-dimensional finite-difference time-domain (3D-FDTD) simulations, high Q-factors above 1 × 106 of 0th-order mode and 1 × 105 of 1st-order mode can be simultaneously achieved. Next, a well-designed equal power splitter, a power combiner and two EMNCs are introduced to form a PhC dual-channel sensor. Based on a sensing matrix, each channel of DCS (EMNC-1 and EMNC-2) can be used in simultaneous detection of refractive index (RI) and temperature independently. Particularly, the total footprint is only about 26. 5 μ m × 6 . 2 μ m × 0 . 22 μ m (length × width × high), which is potentially a promising platform for complex optical multi-sensing network in large scale.

In this paper, a thin-core fiber-based in-line Mach–Zehnder interferometer is theoretically and experimentally demonstrated, and a high sensitivity consistency of temperature (>0.995) is obtained owing to the formed single modal interference. Furthermore, the nonlinear wavelength-dependence of elastic-optical coefficient is characterized, and a sharp intensity inversion between the macro- and micro-bending states is experimentally observed. Then, a novel dual-differential compensation (DDC) method is proposed to eliminate the temperature errors in the measured curvature and strain. By means of DDC, the variations of curvature and strain can be simultaneously detected and discriminated without the crosstalk of ambient temperature, and the corrected sensitivities, respectively, reach −17.67 nm/m−1 and −1.92 pm/ $\mu \varepsilon $ . This fabricated sensor is very practical and promising for the accurate measurement of multiple parameters.

We investigate the influence of mode coupling on space division multiplexing capability of three multimode step-index plastic optical fibers with different strengths of mode coupling. Results show that mode coupling significantly limits the fiber length at which the space division multiplexing can be realized with a minimal crosstalk between the neighbor optical channels. Three, four and five spatially multiplexed channels in the investigated multimode step-index plastic optical fibers can be employed with a minimal crosstalk up to the fiber lengths which are about 7%, 5% and 3% of the corresponding coupling lengths (fiber length where equilibrium mode distribution is achieved), respectively. Such characterization of optical fibers should be considered in designing an optical fiber transmission system for space division multiplexing.

In this article, a method for evaluating the implications of threshold voltage ( VTH ) drift from gate voltage stress in SiC MOSFET s is presented. By exploiting the Miller coupling between two devices in the same phase leg, the technique uses the shoot-through charge from parasitic turn- on to characterize the impact of bias temperature instability (BTI)-induced VTH shift. Traditional methods of BTI characterization rely on the application of a stress voltage without characterizing the implication of the VTH shift on the switching characteristics of the device in a circuit. Unlike conventional methods, this method uses the actual converter environment to investigate the implications of VTH shift and should therefore be of more interest to applications engineers as opposed to device physicists. Furthermore, a common problem is the underestimation of the VTH shift since recovery from charge detrapping can mask the true extent of the problem. The impact of temperature, the recovery time after stress removal, and polarity of the stress has been studied for a set of commercially available SiC MOSFET s.

The multi-reflection crosstalk when combined with the spectral-shadowing effect has been shown to make the interpretation of spectral analysis more difficult in Phase-OTDR sensing system based on weak fiber Bragg grating array.

The polarization-maintaining fiber-based Sagnac loop interferometer (PSLI) is frequently applied in directional torsion measurement, but may suffer from a large temperature cross talk. In this study, a novel method was proposed for fabrication of side-tapered PSLI by a two-step arc-discharge technique at the splicing point. The energy distribution of the taper region was characterized, and comprehensive tests were performed in terms of torsion and temperature. The experimental results showed that, through bias twisting, the measuring areas were effectively gapped and highly sensitive torsion and temperature responses were gained simultaneously. With a small wavelength shift, the torsion sensitivity reached 13.54 dB/rad in the range from − 30 to 30 rad/m. Moreover, the temperature sensitivity was found to be − 1.579 n m / ∘ C , with a near-zero intensity fluctuation. Therefore, the sensor fabricated herein successfully achieves simultaneous measurement of directional torsion and temperature with high sensitivity and ultralow cross talk. The proposed scheme has the merits of practicality, low cost, and ease of operation, and is very promising for multiparameter engineering monitoring.