English
Related papers

Related papers: Adiabatic quantum pumping in graphene with magneti…

200 papers

We devise a quantum-circuit algorithm to solve the ground state and ground energy of artificial graphene. The algorithm implements a Trotterized adiabatic evolution from a purely tight-binding Hamiltonian to one including kinetic,…

We study the pump current and noise properties in an adiabatically modulated magnetic nanowire with double domain walls (DW). The modulation is brought about by applying a slowly oscillating magnetic and electric fields with a controllable…

Mesoscale and Nanoscale Physics · Physics 2016-09-08 Rui Zhu , Jamal Berakdar

We study the transmission probability of Dirac fermions in graphene scattered by a triangular double barrier potential in the presence of an external magnetic field. Our system made of two triangular potential barrier regions separated by a…

Mesoscale and Nanoscale Physics · Physics 2015-11-24 Miloud Mekkaoui , Ahmed Jellal , Hocine Bahlouli

We derived a general and exact expression of current for quantum parametric charge pumps in the non-adiabatic regime at finite pumping frequency and finite driving amplitude. The non-perturbative theory predicts a remarkable plateau…

Condensed Matter · Physics 2009-11-07 Baigeng Wang , Jian Wang , Hong Guo

We obtain the solution of the Dirac equation in (2+1) dimensions in the presence of a constant magnetic field normal to the plane together with a two-dimensional Dirac-oscillator potential coupling. We study the energy spectrum of graphene…

Mesoscale and Nanoscale Physics · Physics 2016-02-17 Abdelhadi Belouad , Ahmed Jellal , Youness Zahidi

Controlled charge pumping in an AlGaAs/GaAs gated nanowire by single-parameter modulation is studied experimentally and theoretically. Transfer of integral multiples of the elementary charge per modulation cycle is clearly demonstrated. A…

Mesoscale and Nanoscale Physics · Physics 2008-04-15 B. Kaestner , V. Kashcheyevs , S. Amakawa , L. Li , M. D. Blumenthal , T. J. B. M. Janssen , G. Hein , K. Pierz , T. Weimann , U. Siegner , H. W. Schumacher

We develop a theory for the compressibility and quantum capacitance of disordered monolayer and bilayer graphene including the full hyperbolic band structure and band gap in the latter case. We include the effects of disorder in our theory,…

Mesoscale and Nanoscale Physics · Physics 2011-03-09 D. S. L. Abergel , E. H. Hwang , S. Das Sarma

We study adiabatic charge pumping through a quantum dot placed at the junction of $N$ quantum wires. We explicitly map out the pattern of pumped charge as a function of the time-varying tunneling parameters coupling the wires to the dot and…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Shamik Banerjee , Anamitra Mukherjee , Sumathi Rao , Arijit Saha

We calculate adiabatic charge and spin pumping through a serial double quantum dot with strong Coulomb interaction, coupled to normal metal or ferromagnetic contacts. We use a real-time diagrammatic approach in the regime of weak coupling…

Mesoscale and Nanoscale Physics · Physics 2010-12-13 Roman-Pascal Riwar , Janine Splettstoesser

We present a quantum-mechanical model that describes fiber-based frequency conversion by four-wave-mixing Bragg scattering in the presence of Raman interactions. In the case of continuous-wave pumps we find closed-form expressions for the…

Quantum Physics · Physics 2024-06-06 Mathias Linde Holst Korsgaard , Jacob Gade Koefoed , Karsten Rottwitt

A d.c. current can be pumped through a quantum dot by periodically varying two independent parameters $X_1$ and $X_2$, like a gate voltage or magnetic field. We present a formula that relates the pumped current to the parametric derivatives…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 P. W. Brouwer

We consider a classical overdamped Brownian particle moving in a symmetric periodic potential. We show that a net particle flow can be produced by adiabatically changing two external periodic potentials with a spatial and a temporal phase…

Statistical Mechanics · Physics 2009-11-07 O. Usmani , E. Lutz , M. Buttiker

The transfer of conserved charges through insulating matter via smooth deformations of the Hamiltonian is known as quantum adiabatic, or Thouless, pumping. Central to this phenomenon are Hamiltonians whose insulating gap is controlled by a…

Mesoscale and Nanoscale Physics · Physics 2017-01-04 Pedro L. S. Lopes , Pouyan Ghaemi , Shinsei Ryu , Taylor L. Hughes

We study directed transport in periodically forced scattering systems in the regime of fast and strong driving where the dynamics is mixed to chaotic and adiabatic approximations do not apply. The model employed is a square potential well…

Mesoscale and Nanoscale Physics · Physics 2012-10-04 A. Castañeda , T. Dittrich , G. Sinuco

We report on the possibility of valley number fractionalization in graphene with a topological defect that is accounted for in Dirac equation by a pseudomagnetic field. The valley number fractionalization is attributable to an imbalance on…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 Angel E. Obispo , Marcelo Hott

Two-dimensional materials (2DMs) are fundamentally electro-mechanical systems. Their environment unavoidably strains them and modifies their quantum transport properties. For instance, a simple uniaxial strain could completely turn off the…

Mesoscale and Nanoscale Physics · Physics 2024-04-30 A. C. McRae , G. Wei , L. Huang , S. Yigen , V. Tayari , A. R. Champagne

We utilize a time-periodic ratchet-like potential modulation imposed onto a two-dimensional electron system inside a GaAs/Al$_x$Ga$_{1-x}$As heterostructure to evoke a net dc pumping current. The modulation is induced by two sets of…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 T. Mueller , A. Wuertz , A. Lorke , D. Reuter , A. D. Wieck

Graphene, with its quantum Hall topological (Chern) number reflecting the massless Dirac particle, is shown to harbor yet another topological quantum number. This is obtained by combining Streda's general formula for the polarization…

Mesoscale and Nanoscale Physics · Physics 2015-03-30 Hideo Aoki , Yasuhiro Hatsugai

A spin strongly driven by two harmonic incommensurate drives can pump energy from one drive to the other at a quantized average rate, in close analogy with the quantum Hall effect. The pumping rate is a non-zero integer in the topological…

Mesoscale and Nanoscale Physics · Physics 2020-09-02 Philip J. D. Crowley , Ivar Martin , Anushya Chandran

We investigate non-adiabatic electron pumping in graphene generated by laser irradiation with linear polarization parallel or perpendicular to the transport direction. Transport is dominated by the spatially asymmetric excitation of…

Mesoscale and Nanoscale Physics · Physics 2012-10-12 Pablo San-Jose , Elsa Prada , Henning Schomerus , Sigmund Kohler