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Related papers: Semiclassical theory of a quantum pump

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We study a one-dimensional quantum pump composed of two oscillating delta-functional barriers. The linear and non-linear regimes are considered. The harmonic signal applied to any or both barriers causes the stationary current. The…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 M. M. Mahmoodian , L. S. Braginskii , M. V. Entin

A ballistic atom pump is a system containing two reservoirs of neutral atoms or molecules and a junction connecting them containing a localized time-varying potential. Atoms move through the pump as independent particles. Under certain…

Quantum Gases · Physics 2015-11-23 Tommy A. Byrd , Kunal K. Das , Kevin A. Mitchell , Seth Aubin , John B. Delos

We propose three different mechanisms for pumping spin-polarized currents in a ballistic circuit using a time-dependent magnetic field acting on an asymmetrically connected quantum ring at half filling. The first mechanism works thanks to a…

Mesoscale and Nanoscale Physics · Physics 2014-02-26 Michele Cini , Stefano Bellucci

By using numerical and semiclassical methods, we evaluate the quantum breaking, or Ehrenfest time for a wave packet localized around classical equilibrium points of autonomous one-dimensional systems with polynomial potentials. We find that…

Quantum Physics · Physics 2009-11-07 Fabrizio Cametti , Carlo Presilla

We investigate the parametric pumping of a hybrid structure consisting of a normal quantum dot, a normal lead and a superconducting lead. Using the time dependent scattering matrix theory, we have derived a general expression for the pumped…

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

We examine a classically-chaotic system consisting of two reservoirs of particles connected by a channel containing oscillating potential-energy barriers. We investigate whether such a system can preferentially pump particles from one…

The adiabatic pumped current through an unbiased one dimensional (1D) channel, connected to two 1D leads and subject to surface acoustic waves (SAW), is calculated exactly for non-interacting electrons. For a broad range of the parameters,…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Amnon Aharony , O. Entin-Wohlman

We investigate spin and charge current through a quantum dot pumped by a time-varying magnetic field. Using the density matrix method, quantum rate equations for the electronic occupation numbers in the quantum dot are obtained and solved…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Zhao Yang Zeng , Hong Li , Baowen Li

We propose schemes for generating spin currents into a semiconductor by adiabatic or non-adiabatic pumping of electrons through interacting quantum dots. The appeal of such schemes lies in the possibility to tune the pumping characteristics…

Mesoscale and Nanoscale Physics · Physics 2015-01-09 Stephan Rojek , Michele Governale , Jürgen König

We propose a new mode of operation of an electron pump consisting of two weakly coupled quantum dots connected to reservoirs. An electron can be transferred within the device at zero bias voltage when it is subjected to electromagnetic…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 B. L. Hazelzet , M. R. Wegewijs , T. H. Stoof , Yu. V. Nazarov

We study single-parameter quantized charge pumping via a semiconductor quantum dot in high magnetic fields. The quantum dot is defined between two top gates in an AlGaAs/GaAs heterostructure. Application of an oscillating voltage to one of…

Mesoscale and Nanoscale Physics · Physics 2009-01-21 B. Kaestner , Ch. Leicht , V. Kashcheyevs , K. Pierz , U. Siegner , H. W. Schumacher

The topological property in one dimension (1D) is protected by symmetry. Based on a concrete model, we show that since a 1D topological model usually contain two of the three Pauli matrix, the left one automatically become the protecting…

Mesoscale and Nanoscale Physics · Physics 2016-04-21 Jihong Qin , Huaiming Guo

We consider pumping through a small quantum dot separated from the leads by two point contacts, whose conductances, $G_{1}$ and $G_{2}$, serve as pumping parameters. When the dot is pincched, we find that there is a "resonance line" in the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Y. Levinson , O. Entin-Wohlman , P. Wolfle

We study electron pumping through a system of barriers, whose heights are deformed adiabatically. We derive a simple formula for the pumped charge $Q$ in terms of the total reflection and transmission amplitudes and phases. The pumped…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Argha Banerjee , Sourin Das , Sumathi Rao

We study the quantum spin pumping of an antiferromagnetic spin-1/2 chain with competing exchange interactions. We show that spatially periodic potential modulated in space and time acts as a quantum spin pump. In our model system, an…

Strongly Correlated Electrons · Physics 2009-11-13 Sujit Sarkar , C. D. Hu

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…

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

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

The acoustoelectric current induced by a surface acoustic wave (SAW) in a ballistic quantum point contact is considered using a quantum approach. We find that the current is of the "pumping" type and is not related to drag, i.e. to the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Y. Levinson , O. Entin-Wohlman , P. Woelfle

Recently a new explanation for the quantized current of the surface acoustic wave (SAW)-driven single electron pumps was suggested [1]. In the SAW-driven pumps the electrons are transported by the SAW along a one-dimensional semiconductor…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 V. I. Talyanskii

In a mesoscopic system, under zero bias voltage, a finite charge is transferred by quantum adiabatic pumping by adiabatically and periodically changing two or more control parameters. We obtained expressions for the pumped charge for a ring…

Mesoscale and Nanoscale Physics · Physics 2016-09-22 Masahiko Taguchi , Satoshi Nakajima , Toshihiro Kubo , Yasuhiro Tokura