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We derive a complete set of expressions for the MOSFET gate and drain power spectral densities due to elastic and inelastic trapping/detrapping of channel carriers into the gate dielectric. Our calculations explain trapping/detrapping noise (TDN) in various FET operating regions and highlight trap’s position-dependent terms, often neglected in the literature, which are instead important for devices with thin gate dielectrics. Furthermore, we show that TDN has a contribution to the gate current noise, correlated with the drain current fluctuations and we highlight the role of the transfer function between channel charge fluctuations and drain current on the noise characteristics. The model expressions are carefully validated by comparison with 2-D and 3-D TCAD simulations of scaled MOSFETs with different architectures (bulk, fully depleted-silicon-on-insulator (FD-SOI), FinFET), channel, and gate materials. Besides shedding new light on TDN, the results could enable trap density extraction from experimental samples with improved accuracy and pave the way to complete and accurate compact models for TDN in MOSFETs.

Bank loans can convey information about the borrowing firms that have proper corporate governance systems. Using a sample of bank loan announcements in China, we find that the market reaction is positive after the split share structure reform in 2005, which aligns the interests of large shareholders and minority shareholders, government and public investors, and alleviates their tunneling incentives. We also find that this effect is more pronounced for private firms as the reform mainly enhances corporate governance for private firms. The signaling role of bank loans is less pronounced for firms with less severe information asymmetry after the reform, e.g. higher shareholdings of mutual funds and higher proportion of independent directors. Related party transactions decrease when they obtain bank loans after the reform, which reflects the alleviation of tunneling after the reform.

Tunnel is a technique of building a local communication path between two or more routers using a public IP network. The problems faced in tunneling systems are currently lacking guidelines for choosing the right technique according to the network topology used. In the electoral field, it is done based on experience or following SOPs. The brands of devices that support tunneling are very diverse in Indonesia, one of which is Nokia. This study focuses on the tunnel owned by Nokia devices, namely the GRE in order to produce guidelines for using the GRE tunnel. The analysis is carried out with various traffic engineering scenarios including no-load conditions, and various other conditions when there is a network outage. The results showed that the GRE without load runs normally. When the load from the beginning of the GRE gets a throughput of 0.995 Mbps and an average delay of 11.484 ms, when with a sudden load it gets a throughput of 1.059 Mbps and a delay of 11.386 and when a network disturbance is carried out with the ping command it gets 1 RTO. The GRE tunnel follows the LDP protocol path so it is suitable for use in new network implementations because of its simplicity in its configuration which is enough to activate the OSPF metric to balance traffic on each particular router interface

Relevance. One of the key points in plasty of the anterior cruciate ligament (ACL) is the isometric position of the graft, in which its tension remains the same during flexion and extension of the knee joint. However, no method has been described today for the intraoperative determination of the isometricity of the location of the femoral and tibial tunnels (for placing the graft) before their formation.Purpose of the study. To develop a method for intraoperative determination of the isometricity of the location of the femoral and tibial tunnels before their formation during ACL plasty and to study its effectiveness.Material and methods. The study included 30 patients who underwent ACL repair. For a preliminary intraoperative assessment of the isometric areas of graft fixation on the femur and tibia, the proposed original method with the use of two knot pushers and a thread passing through them. Isometry was assessed by the degree of displacement of this thread. After determining the isometric areas of fixation, the femoral and tibial tunnels were formed, and the isometric position of the graft before its fixation in the tibia was checked by the degree of displacement of the threads with which the graft was sutured relative to the aperture of the tibial tunnel.Results. The average displacement of the thread relative to the pusher of the knot in the preliminary determination of the isometric areas of fixation according to the proposed method corresponded to the displacement of the threads with which the distal end of the graft was sewn relative to the outer aperture of the tibial tunnel (this value did not exceed 2 mm on average) until the final fixation of the graft in the tibial tunnel.Conclusion. The developed method makes it possible to determine the isometric location of the femoral and tibial tunnels during arthroscopic plasty of the anterior cruciate ligament before their formation. If the location of the fixation points on the femur and tibia is determined non-isometric, it is possible to correct their position.

The growth of volume of tunneling, power supplied per job, and consumption of fuel and energy resources makes it necessary to increase energy performance of production processes with reducing energy losses. Tunneling conditions are determined by a combination of mutually influencing factors (geological, technological and organizational), and assessing their impact on tunneling energy performance requires a deep detailed study. For criterion assessment of tunneling performance, indicators of energy consumption, performance, and quality of tunneling performed by shift crews, allowing to objectively assess their work, were proposed. Indicators of process and specific power consumption in the process of tunneling vary over a wide range, therefore, to ensure smooth equipment operation, shift crews must adhere to the recommended indicators that determine the optimum rates of tunneling and enables adherence to permissible operation modes. Statistical models of energy performance indicators of heading sets of equipment operation were investigated using the example of the Severnaya coal mine. Indicators of energy consumption, energy performance, and tunneling (on shift basis) were proposed. Distribution laws have been determined for the main indicators characterizing tunneling energy performance. Recommendations have been developed to ensure sustainable operation of heading sets of equipment throughout the entire period of tunneling. Tunneling requires permanent monitoring its parameters and rates of advance, the quality of face preparation, timely maintenance and repair of machinery and equipment, control of the process through ensuring optimal operating modes of the heading sets of equipment.

Gallium Nitride (GaN) based light-emitting diodes (LEDs) are being utilized in an ever expanding number of applications. The persistent issues, however, have been the use of alternating current (AC) to direct current (DC) converters and the inefficient p-type doping compared to n-type doping. Here, a novel hybrid AC InGaN quantum well (QW) LED without a p-GaN layer is demonstrated at 450 nm. A tunneling LED is fabricated through use of InGaN QWs, combined with a thin Al2O3 dielectric with NiO as the source of the holes. This hybrid InGaN LED utilizes Fowler-Nordheim tunneling and band bending in order to inject holes into the active region. Due to the symmetric nature of the tunneling, hole or electron injection through the top oxide layer leads to AC performance. Room temperature and cryogenic I-V measurements are performed to evaluate the tunneling mechanism. Tunneling of holes is found to lead to earlier device turn-on of ~0.5 V compared with conventional blue LEDs at ~2 V. The presented work can lead to a number of novel applications such as on-chip communication, monolithic integration with transistors, and LiFi.

Quasi-two-dimensional perovskites have emerged as a new material platform for optoelectronics on account of its intrinsic stability. A major bottleneck to device performance is the high charge injection barrier caused by organic molecular layers on its basal plane, thus the best performing device currently relies on edge contact. Herein, by leveraging on van der Waals coupling and energy level matching between two-dimensional Ruddlesden-Popper perovskite and graphene, we show that the plane-contacted perovskite and graphene interface presents a lower barrier than gold for charge injection. Electron tunneling across the interface occurs via a gate-tunable, direct tunneling-to-field emission mechanism with increasing bias, and photoinduced charge transfer occurs at femtosecond timescale (~50 fs). Field effect transistors fabricated on molecularly thin Ruddlesden-Popper perovskite using graphene contact exhibit electron mobilities ranging from 0.1 to 0.018 cm2V−1s−1 between 1.7 to 200 K. Scanning tunneling spectroscopy studies reveal layer-dependent tunneling barrier and domain size on few-layered Ruddlesden-Popper perovskite., Insulating molecular layers on the basal plane of 2D perovskite is a major bottleneck for charge injection that limiting device performance. Here, the authors show that plane-contacted graphene functions as a low barrier and gate-tunable contact to overcome this limitation.

A fully analytical surface potential and current–voltage model is presented for the first time for both lateral homojunction (HMJ) and heterojunction (HTJ) tunneling-field-effect transistors (TFETs) based on 2-D semiconducting channel materials. The dynamic gate-modulated electrostatic potential at the source/channel tunneling junction is suitably captured by solving a quasi-2-D Poisson’s equation in both source and channel. Subsequently, the band-to-band tunneling current is accurately derived starting from the Landauer’s equation by integrating over all possible carrier energies (or wave-vectors) over which tunneling is possible. The model employs Fermi–Dirac statistics in both the degenerate source and drain to compute the surface potential and net current, which yields more physical results than the commonly employed Boltzmann statistics. Its use in Landauer’s approach for evaluating the net ON-current leads to an analytical model of the TFET, which physically guarantees zero drain current at zero drain–source bias. Input and output characteristics for both HMJ and HTJ TFETs are computed and compared against rigorous nonequilibrium Green’s function (NEGF) simulations for different device parameters to prove the veracity of the model, and the match has been found to be excellent up to ultrashort channel length of 5 nm.

This study investigates the influence of related party transactions (RPTs) on firm value. Further, it examines whether a firm’s corporate social responsibility (CSR) reporting reflects its corporate values and ethical concerns, therefore mitigating the value-destroying effects of RPTs. Based on 274 observations from publicly listed firms in Indonesia, our results show that RPTs (i.e., related party sales) are negatively related to firm value. Further, we find that in the presence of better CSR reporting, the relationship between RPTs and firm value becomes more positive. This is in line with the view that CSR reporting, which reflects firms’ ethical concerns, may serve as a mechanism against managers’ opportunism. However, we find that related party payables have a positive relationship with firm value. Further investigation reveals that, although certain RPTs show a short-term, value-enhancing effect, these transactions seem to result in subsequent tunneling activities, suggesting managerial opportunism in the long term.

This paper presents a theoretical comparison of the electro-optical characteristics of 850nm GaAs/AlGaAs pin-and BTJ-based VCSELs. The calculations are based on a drift-diffusion model coupled with a NEGF formalism, able to model accurately the tunneling across the TJ. The resulting LIV characteristics demonstrate promising improvements, at both 25 and 80°C, enabled by TJ confinement scheme.

This technical note investigates the effect of footing embedment depth on tunnel-structure interaction using geotechnical centrifuge testing. A two-story framed building on separate footings, either resting directly on the surface or embedded in the soil, and subjected to tunneling induced displacements is modeled. Measurements of the displacements of the footings and underlying soil, ground deformations, and structural distortions are presented. Results show that footing embedment increases foundation differential settlements and horizontal displacements, thereby causing a greater level of distortion within the frame. Furthermore, the embedded footings result in a larger magnitude of ground displacements and shear strains of the soil. Finally, modification factors and relative stiffness parameters are presented, indicating a greater effect of the embedment on horizontal deformations than the angular distortion of the bays.

Terahertz (THz) technology has recently attracted wide scientific and technological interests in quantum science, where the need of fast and sensitive photodetectors prospects fascinating impacts in quantum computing, quantum metrology and optical communications. In this work, we demonstrate that quantum dot single electron transistors (SETs) based on InAs/InAs0.3P0.7 axially heterostructured nanowires integrated with planar on-chip nano-antennas, behave as highly sensitive zero-bias photo-thermoelectric detectors at 0.6 THz. The detector photoresponse can be optimized by electrostatic gating, taking advantage of the SET transport characteristics that clearly reflects energy quantization and single-electron tunneling in the dot.

Tunnel settlement has a significant impact on property security and personal safety. Accurate tunnel-settlement predictions can quickly reveal problems that may be addressed to prevent accidents. However, each acquisition point in the tunnel is only monitored once daily for around two months. This paper presents a new method for predicting tunnel settlement via transfer learning. First, a source model is constructed and trained by deep learning, then parameter transfer is used to transfer the knowledge gained from the source model to the target model, which has a small dataset. Based on this, the training complexity and training time of the target model can be reduced. The proposed method was tested to predict tunnel settlement in the tunnel of Shanghai metro line 13 at Jinshajiang Road and proven to be effective. Artificial neural network and support vector machines were also tested for comparison. The results showed that the transfer-learning method provided the most accurate tunnel-settlement prediction.

An electrically controlled metaswitch is demonstrated by integrating passive metamaterial (metallic-slot array) with well-established nonvolatile flash memory technology [floating-gate (FG) structure]. In this hybrid configuration, the metamaterial acts as its control-gate layer while a monolayer graphene is the FG layer surrounded by insulators. Whose permittivity can be reconfigured with varying carrier density and correspondingly control the transmission of the passive metamaterial. In addition, this reconfiguration can be persistent due to the nonvolatile property of the FG structure (trapped charges). The gate-controllable light-matter interaction in this hybrid configuration can be greatly enhanced due to the strong resonances of the metallic-slot antenna; therefore, 78% ER is achieved by tuning the Fermi level from 0 to 0.4 eV at 0.24 THz. Furthermore, since the resonance frequency is controlled by the geometries of the metamaterial, it can be scaled from near-infrared to the terahertz regimes. The hysteretic behavior indicates new opportunities and versatility for reconfigurable metaswitch, allowing the persistent modification of their unusual electromagnetic responses by transient stimulus.

Mechanical-strain-gated switches are cornerstone components of material-embedded circuits that perform logic operations without using conventional electronics. This technology requires a single material system to exhibit three distinct functionalities: strain-invariant conductivity and an increase or decrease of conductivity upon mechanical deformation. Herein, mechanical-strain-gated electric switches based on a thin-film architecture that features an insulator-to-conductor transition when mechanically stretched are demonstrated. The conductivity changes by nine orders of magnitude over a wide range of tunable working strains (as high as 130%). The approach relies on a nanometer-scale sandwiched bilayer Au thin film with an ultrathin poly(dimethylsiloxane) elastomeric barrier layer; applied strain alters the electron tunneling currents through the barrier. Mechanical-force-controlled electric logic circuits are achieved by realizing strain-controlled basic (AND and OR) and universal (NAND and NOR) logic gates in a single system. The proposed material system can be used to fabricate material-embedded logics of arbitrary complexity for a wide range of applications including soft robotics, wearable/implantable electronics, human-machine interfaces, and Internet of Things. Funding Agencies|Alexander von Humboldt postdoc fellowshipAlexander von Humboldt Foundation; German Science FoundationGerman Research Foundation (DFG) [404941515, SPP 2100]; German Research Foundation (DFG)German Research Foundation (DFG) [MA 5144/9-1, MA 5144/13-1, MA 5144/28-1]; Helmholtz Association of German Research CentresHelmholtz Association [HIL-A04]; Projekt DEAL

The main objective of this article is to provide a general numerical approach for the hydro-mechanical (HM) modelling of tunnels excavated in saturated rock masses exhibiting plastic behaviour, considering a multi-stage excavation process. First, a new excavation method has been proposed and implemented in the software CODE_BRIGHT, based on the finite element method. In this method, the stresses in the excavation elements are reduced smoothly. As verification, the principle of uniqueness has been tested for multi-stage excavation. Then, numerical studies have been carried out to verify the advantages of the proposed excavation method in the numerical calculation, showing that the proposed method improves computational efficiency and mitigates convergence issues. Hence, this method can solve the usual numerical difficulties related to excavation problems and, therefore, it allows a more in-depth analysis of the HM behaviour of rock masses during tunnel excavation. Moreover, the results obtained in CODE_BRIGHT using the proposed method are compared with existing solutions for longitudinal deformation profiles (LDP), including elastic–plastic solutions for mechanical problems and elastic solutions for HM problems. Furthermore, this article presents the HM modelling of tunnels excavated in saturated rock masses, analysing the sensitivity of the LDP to the HM conditions and to the rock mass quality. Finally, based on a large amount of data obtained from numerical simulations, empirical solutions for the LDP of tunnels excavated in saturated rock masses –in a steady-state HM framework– have been obtained by fitting non-linear curves for the normalised radial displacements that occur ahead and behind the tunnel face. Hence, this article attempts to provide a convenient set of alternatives for the preliminary design of tunnels excavated in saturated rock masses., This research was supported by the CODE_BRIGHT Project (International Centre for Numerical Methods in Engineering). The first author was supported by a CSC scholarship (No. 201706260240).

Ferroelectric tunneling junctions (FTJ) are considered to be the intrinsically most energy efficient memristors. In this work, specific electrical features of ferroelectric hafnium-zirconium oxide based FTJ devices are investigated. Moreover, the impact on the design of FTJ-based circuits for edge computing applications is discussed by means of two example circuits.

Underground tunneling results in redistribution of the in-situ stress state. This process can create unstable underground conditions. Tunnel instability can result in fatalities, property damages, project delays, high rehabilitation cost, and can compromise the overall functionality of the excavation. This study assesses the efficiency of the empirically recommended support design of the Pahang-Selangor Water Transfer Tunnel in Peninsular, Malaysia using convergence-confinement (CV-CF) and 2-Dimensional two-dimensional Finite Element Method (FEM). To reduce the effect of subjective uncertainties associated with the rock mass rating system, the lump rating system was replaced with the continuous rating system to classify the rock masses and provide empirical support design for the tunnel. The maximum capacity and stiffness of the support systems were analytically determined using the CV-CF method. The results of the maximum elastic deformation of the support systems were compared to the actual critical internal pressures which show that the empirically recommended support systems can satisfactorily stabilize the underground excavation. The Reliability of the support design, the plastic zones, and total deformations were determined using Phase2. The radius of plastic zones and the maximum total deformations were significantly reduced after the supports were installed. The plastic zones that remained were restricted within the reinforced zones, signifying the effectiveness of the recommended support systems.

An accurate procedure for coupling (time-dependent) driven electron tunneling and electromagnetic propagation at terahertz frequencies cannot be developed neither with equivalent electric-circuit approximations nor using standard electromagnetic solvers. Alternatively, in this work, a full-physical time-dependent self-consistent algorithm for such coupling is presented. In order to demonstrate the numerical viability of the algorithm and to show the great interest of driven electron tunneling devices for terahertz applications, a transistorlike tunneling device (coupled to lossy transmission lines) is designed for developing a rectifier, a harmonic generator, and an amplitude modulator at terahertz frequencies.

Defects can significantly modify the electro-optical characteristics of InGaN light-emitting diodes (LEDs); however, modeling the impact of defects on the electrical characteristics of LEDs is not straightforward. In this paper, we present an extensive investigation and modeling of the impact of defects on the electrical characteristics of InGaN-based LEDs, as a function of the thickness of the quantum well (QW). First, we demonstrate that the density of defects in the active region of III-N LEDs scales with increasing thickness of the InGaN QW. Since device layers with high indium content tend to incorporate more defects, we ascribed this experimental evidence to the increased volume of defects-rich InGaN associated to thicker InGaN layers. Second, we demonstrate that the current-voltage characteristics of the devices are significantly influenced by the presence of defects, especially in the sub turn-on region. Specifically, we show that the electrical characteristics can be effectively modeled in a wide current range (from pA to mA), by considering the existence of trap-assisted tunneling processes. A good correspondence is obtained between the experimental and simulated electrical characteristics (I-V), by using – in the simulation – the actual defect concentrations/activation energies extracted from steady-state photocapacitance, instead of generic fitting parameters.