V. Vyurkov, V. Ryzhii
In the recent paper [arXiv:0802.2216, 15 Feb 2008], Kashuba argued that the intrinsic conductivity of graphene independent of temperature originated in strong electron-hole scattering. We propose a much more explicit derivation based on a scaling theory approach. We also give an explanation of a rapid increase in graphene conductivity caused by applied gate voltage.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
继续探索
Observations of terahertz loss to gain switching in transmission through gates on biased graphene sandwiches are explained by response under electron streaming in graphene. Basing on this consideration the terahertz source is proposed consisting of silicon resonator placed on the sandwich with current flow in graphene. It should provide tunable by bias emission in wide terahertz band. The source is direct terahertz analog of tunable microwave laser demonstrated.
We calculate the intrinsic spin Hall conductivity σ^{\mathrm{sH}} of a two-dimensional electron system within a generalized Rashba model, showing that it is, in general, finite and model-dependent. Considering arbitrary band dispersion, we find that σ^{\mathrm{sH}} in the presence of the linear-in-momentum spin-orbit coupling of the Rashba form does not vanish in the presence of impurities except for the precisely parabolic spectrum. We show, using the linear response Kubo formalism, how the exact cancellation happens for the quadratic dispersion, and why it does not occur in general. We deriv…
Optical-pump terahertz-probe spectroscopy is used to investigate ultrafast far-infrared conductivity dynamics during the insulator-to-metal transition (IMT) in vanadium sesquioxide (V2O3). The resultant conductivity increase occurs on a tens of ps timescale, exhibiting a strong dependence on the initial temperature and fluence. We have identified a scaling of the conductivity dynamics upon renormalizing the time axis with a simple power law (alpha = 1/2) that depends solely on the initial, final, and conductivity onset temperatures. Qualitative and quantitative considerations indicate that the…
We study theoretically an influence of the near-interfacial insulator traps and electron-hole puddles on the small-signal capacitance and conductance characteristics of the gated graphene structures. Based on the self-consistent electrostatic consideration and taking into account the interface trap capacitance the explicit analytic expressions for charge carrier density and the quantum capacitance as functions of the gate voltage were obtained. This allows to extract the interface trap capacitance and density of interface states from the gate capacitance measurements. It has shown that self-co…
In framework of classical consideration of electron trajectories in crossed electric and magnetic fields and conductivity of electron system on cyclotron resonance in single layer graphene possibility to achieve cyclotron lasing in hexagonal boron nitride single layer graphene sandwiches is discussed. By simplified consideration with known data on scattering rate in the sandwiches it is demonstrated that the continuing wave laser action can be achieved in high quality sandwiches at room temperature at frequencies above one tera hertz in magnetic field above one Tesla.
Problem of nonlinear conductivity within relaxation time approximation in noncentrosymmetric insulators
本文提出了一种基于Redfield方程改进的RTA方法，用于研究非中心对称绝缘体中的非线性导电性问题。
We discuss the effect of disorder on the band gap measured in bilayer graphene in optical and transport experiments. By calculating the optical conductivity and density of states using a microscopic model in the presence of disorder, we demonstrate that the gap associated with transport experiments is smaller than that associated with optical experiments. Intrinsic bilayer graphene has an optical conductivity in which the energy of the peaks associated with the interband transition are very robust against disorder and thus provide an estimate of the band gap. In contrast, extraction of the ban…
There is a wide range of science and applications accessible via the strain engineering of quantum transport in 2D materials. We propose a realistic experimental platform for uniaxial strain engineering of ballistic charge transport in graphene. We then develop an applied theoretical model, based on this platform, to calculate charge conductivity and demonstrate graphene quantum strain transistors (GQSTs). We define GQSTs as mechanically strained ballistic graphene transistors with on/off conductivity ratios $> 10^{4}$, and which can be operated via modest gate voltages. Such devices would per…
We study the characteristics of photogenerated electron-hole plasma in optically pumped graphene layers at elevated (room) temperatures when the interband and intraband processes of emission and absorption of optical phonons play a crucial role. The electron-hole plasma heating and cooling as well as the effect of nonequilibrium optical phonons are taken into account. % The dependences of the quasi-Fermi energy and effective temperature of optically pumped graphene layers on the intensity of pumping radiation are calculated. The variation of the frequency dependences dynamic conductivity with …
Unconventional optical response in monolayer graphene upon dominant intraband scattering
本文利用半经典多带玻尔兹曼方程研究单层石墨烯中散射对光学电导率的影响，发现低掺杂下主导带内散射导致其线性光学响应显著偏离普适电导率，并建立了与Kubo方法一致的解析理论。
We present a detailed numerical study of the electronic transport properties of bilayer and trilayer graphene within a framework of single-electron tight-binding model. Various types of disorder are considered, such as resonant (hydrogen) impurities, vacancies, short- or long-range Gaussian random potentials, and Gaussian random nearest neighbor hopping. The algorithms are based on the numerical solution of the time-dependent Schr ödinger equation and applied to calculate the density of states and conductivities (via the Kubo formula) of large samples containing millions of atoms. In the cases…
We show how intrinsic material properties modify light transmission through subwavelength hole arrays on thin metallic films in the THz regime. We compare the temperature-dependent transmittance of Au films and MgB$_{2}$ films. The experimental data is consistent with analytical calculations, and is attributed to the temperature change of the conductivity of both films. The transmission versus conductivity is interpreted within the open resonator model when taking the skin depth into consideration. We also show that the efficiency of this temperature control depends on the ratio of the transmi…
扫码添加微信好友，提出您的宝贵建议 👇
💡 备注请填写：网站反馈
发表机构由 AI 从论文文本抽取，如发现错误，欢迎反馈修正建议。