Biasing

About: Biasing is a research topic. Over the lifetime, 29422 publications have been published within this topic receiving 301035 citations.

Enhanced Magnetotransport at High Bias in Quasimagnetic Tunnel Junctions with EuS Spin-Filter Barriers

Abstract: In quasimagnetic tunnel junctions with a EuS spin-filter tunnel barrier between Al and Co electrodes, we observed large magnetoresistance (MR). The bias dependence shows an abrupt increase of MR ratio in high bias voltage, which is contrary to conventional magnetic tunnel junctions. This behavior can be understood as due to Fowler-Nordheim tunneling through the fully spin-polarized EuS conduction band. The I-V characteristics and bias dependence of MR calculated using tunneling theory show excellent agreement with experiment.

Low voltage differential swing interconnect buffer circuit

Abstract: A low voltage differential swing interconnect I/O buffer within an output buffer part comprising a voltage controlled current source, voltage controlled current sink, and a current switch and an input buffer part comprising a voltage controlled resistance. The output current and input resistance of the I/O buffer is determined by biasing voltages which are generated by on-chip reference circuits and applied to the voltage controlled components of the I/O buffer. Using two input reference voltages and a single reference resistor, the reference circuits dynamically adjust the biasing voltages so that the I/O buffer maintains the required output current and input resistance for all manufacturing process, supply voltage, and chip temperature variations.

Current–Voltage Characteristics of Long-Channel Nanobundle Thin-Film Transistors: A “Bottom-Up” Perspective

Abstract: By generalizing the classical linear response theory of "stick" percolation to nonlinear regime, we find that the drain-current of a nanobundle thin-film transistor (NB-TFT) is described under a rather general set of conditions by a universal scaling formula ID=A/LSxi(LS/LC,rho SLS 2)timesf(VG,VD ), where A is a technology-specific constant, xi is a function of geometrical factors such as stick length LS, channel length LC, and stick density rhoS, and f is a function of drain VD and gate VG biasing conditions This scaling formula implies that the measurement of the full current-voltage characteristics of a "single" NB-TFT is sufficient to predict the performance characteristics of any other transistor with arbitrary geometrical parameters and biasing conditions

Conduction tuning of graphene based on defect-induced localization.

Abstract: The conduction properties of graphene were tuned by tailoring the lattice by using an accelerated helium ion beam to embed low-density defects in the lattice. The density of the embedded defects was estimated to be 2–3 orders of magnitude lower than that of carbon atoms, and they functionalized a graphene sheet in a more stable manner than chemical surface modifications can do. Current modulation through back gate biasing was demonstrated at room temperature with a current on–off ratio of 2 orders of magnitude, and the activation energy of the thermally activated transport regime was evaluated. The exponential dependence of the current on the length of the functionalized region in graphene suggested that conduction tuning is possible through strong localization of carriers at sites induced by a sparsely distributed random potential modulation.

High performance bias-selectable three-color Short-wave/Mid-wave/Long-wave Infrared Photodetectors based on Type-II InAs/GaSb/AlSb superlattices

Abstract: We propose a new approach in device architecture to realize bias-selectable three-color shortwave-midwave-longwave infrared photodetectors based on InAs/GaSb/AlSb type-II superlattices. The effect of conduction band off-set and different doping levels between two absorption layers are employed to control the turn-on voltage for individual channels. The optimization of these parameters leads to a successful separation of operation regimes; we demonstrate experimentally three-color photodiodes without using additional terminal contacts. As the applied bias voltage varies, the photodiodes exhibit sequentially the behavior of three different colors, corresponding to the bandgap of three absorbers. Well defined cut-offs and high quantum efficiency in each channel are achieved. Such all-in-one devices also provide the versatility of working as single or dual-band photodetectors at high operating temperature. With this design, by retaining the simplicity in device fabrication, this demonstration opens the prospect for three-color infrared imaging.