Related papers: Resonant single-parameter pumping in graphene

A Floquet scattering approach to parametric electron pumps is presented and compared with Brouwer's adiabatic scattering approach [Phys. Rev. B 58, R10135 (1998)] for a simple scattering model with two harmonically oscillating…

We have developed a scattering matrix approach to coherent transport through an adiabatically driven conductor based on photon-assisted processes. To describe the energy exchange with the pumping fields we expand the Floquet scattering…

In this work we derive a general formula for the charge pumped in a superconducting nanocircuit. Our expression generalizes previous results in several ways, it is applicable both in the adiabatic and in the non-adiabatic regimes and it…

Charge-charge, current-current and Raman correlation functions are derived in a consistent way using the unified response theory. The theory is based on the improved description of the conduction electron coupling to the external…

We study a possible circuit solution to overcome the problem of low voltage gain of short-channel graphene FETs. The circuit consists of a fully differential amplifier with a load made of a cross-coupled transistor pair. Starting from the…

Single-electron pumps based on isolated impurity atoms have recently been experimentally demonstrated. In these devices the Coulomb potential of an atom creates a localised electron state with a large charging energy and considerable…

Periodically driven systems, which can be described by Floquet theory, have been proposed to show characteristic behavior that is distinct from static Hamiltonians. Floquet theory proposes to describe such periodically driven systems in…

Non-adiabatic charge pumping through a single-level quantum dot with periodically modulated parameters is studied theoretically. By means of a quantum-master-equation approach the full counting statistics of the system is obtained. We find…

We have performed scanning gate microscopy (SGM) on graphene field effect transistors (GFET), using a biased metallic nanowire coated with a dielectric layer as a contact mode tip and local top gate. Electrical transport through graphene at…

The current carried by a material subject to an electric field is microscopically inhomogeneous and can be modelled using scattering theory, in which electrons undergo collisions with the microscopic objects they encounter. We herein…

Graphene is an ideal platform to study the coherence of quantum interference pathways by tuning doping or laser excitation energy. The latter produces a Raman excitation profile that provides direct insight into the lifetimes of…

We report on a first principles theory for analyzing the parametric electron pump at a finite frequency. The pump is controlled by two pumping parameters with phase difference $\phi$. In the zero frequency limit, our theory predicts the…

Topological charge pumping occurs in the adiabatic limit, and the non-adiabatic effect due to finite ramping velocity reduces the pumping efficiency and leads to deviation from quantized charge pumping. In this work, we discuss the relation…

We report on the observation of the ratchet effect -- generation of direct electric current in response to external terahertz (THz) radiation -- in bilayer graphene, where inversion symmetry is broken by an asymmetric dual-grating gate…

We present a numerical approach for the solution of electromagnetic scattering from a dielectric cylinder partially covered with graphene. It is based on a classical Fourier-Bessel expansion of the fields inside and outside the cylinder to…

We investigate the heat flow in the parametric quantum pump. Using the time dependent scattering matrix theory, we have developed a general theory for the pumped heat current at finite pumping amplitude and frequency. We have applied our…

We report a comprehensive micro-Raman scattering study of electrochemically-gated graphene field-effect transistors. The geometrical capacitance of the electrochemical top-gates is accurately determined from dual-gated Raman measurements,…

Pumping of charge in phase-coherent mesoscopic systems due to the out-of-phase modulation of two parameters has recently found considerable interest. We investigate the effect of inelastic processes on the adiabatically pumped current…

The Schroedinger equation with a potential periodically varying in time is used to model adiabatic quantum pumps. The systems considered may be either infinitely extended and gapped or finite and connected to gapless leads. Correspondingly,…

The independence of the dynamic conductivity of intrinsic graphene of frequency takes its origin in the compensation of the vanishing density of states by the diverging matrix element of the corresponding interband transition. The…