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Related papers: Quantum pumping in helimagnet heterostructures

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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

We theoretically propose quantum spin pumping mediated by magnons, under a time-dependent transverse magnetic field, at the interface between a ferromagnetic insulator and a non-magnetic metal. The generation of a spin current under a…

Mesoscale and Nanoscale Physics · Physics 2012-05-31 Kouki Nakata

We consider quantum pumping of Dirac fermions in a monolayer of graphene in the presence of a perpendicular magnetic field in the central pumping region. The two external pump parameters are electrical voltages applied to the graphene sheet…

Mesoscale and Nanoscale Physics · Physics 2011-01-11 Rakesh P. Tiwari , M. Blaauboer

An understanding of hydrogen diffusion on metal surfaces is important, not just for its role in heterogeneous catalysis and hydrogen fuel cell technology, but also because it provides model systems where tunneling can be studied under…

Chemical Physics · Physics 2014-04-30 Eliza M. McIntosh , K. Thor Wikfeldt , John Ellis , Angelos Michaelides , William Allison

We investigate an adiabatic spin pumping through a quantum dot with a single orbital energy level under the Zeeman effect. Electron pumping is produced by two periodic time dependent parameters, a magnetic field and a difference of the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Tomosuke Aono

In ferromagnet/normal metal heterostructures, spin pumping and spin-transfer torques are two reciprocal processes that occur concomitantly. Their interplay introduces a dynamic feedback effect interconnecting energy dissipation channels of…

Mesoscale and Nanoscale Physics · Physics 2016-08-25 Ran Cheng , Jian-Gang Zhu , Di Xiao

We have investigated the transport characteristics of an electron pump consisting of an asymmetric double quantum dot at zero bias voltage which is subject to electromagnetic radiation. Depending on the energies of the intermediate states…

Mesoscale and Nanoscale Physics · Physics 2008-02-03 T. H. Stoof , Yu. V. Nazarov

In this paper, we propose the quantum spin pumping in quantum spin systems where an applied electric field ($E$) and magnetic field ($H$) cause a finite spin gap to its critical ground state. When these systems are subject to alternating…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Ryuichi Shindou

Spin-pumping experiments in superconductor/ferromagnet heterostructures, which probe spin-sinking by the superconductor, have revealed a variety of complex behaviors. Most studies have focused on conventional s-wave superconductors combined…

We study the pumping effects, in both the adiabatic and nonadiabatic regimes, of a pair of \QTR{it}{finite} finger-gate array (FGA) on a narrow channel. Connection between the pumping characteristics and associated mechanisms is…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. W. Chung , C. S. Tang , C. S. Chu , C. Y. Chang

We present a theory of coherent quantum transport in ferromagnetic/ non-magnetic/ ferromagnetic heterojunctions. We predict quantum coherence to give rise to a quantum spin valve effect that, unlike its familiar classical analog, occurs…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Francisco Mireles , George Kirczenow

We propose a random matrix theory to describe the influence of a time-dependent external field on electron transport through open quantum dots. We describe the generation of the current by an oscillating field for the dot, connected to two…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Maxim G. Vavilov , V. Ambegaokar , Igor L. Aleiner

Tunneling spectroscopy between parallel two-dimensional (2D) electronic systems provides a powerful method to probe the underlying electronic properties by measuring tunneling conductance. In this work, we present a theoretical framework…

Mesoscale and Nanoscale Physics · Physics 2025-09-29 Modi Ke , Mahmoud M. Asmar , Wang-Kong Tse

We study two different parametric pumps for interacting quantum wires, one for pumping spin currents, the other for charge currents. We find that the spin or charge pumped per cycle has a non-universal crossover, depending on pumping…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Prashant Sharma , Claudio Chamon

We describe both experimentally and theoretically a hydrodynamic pumping mechanism in a Fermi liquid, arising from electron-electron interaction. An electron beam sweeping past an aperture is observed to pump carriers from this aperture.…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 J. J. Heremans , A. O. Govorov , D. Kantha , Z. Nikodijevic

Microstrip transducers used for the excitation of spin waves in magnetic films possess two characteristic properties: high spatial localization of the microwave magnetic field and the presence of field components parallel and perpendicular…

Other Condensed Matter · Physics 2010-04-20 T. Neumann , A. A. Serga , V. I. Vasyuchka , B. Hillebrands

Spin pumping is a recently established means for generating a pure spin current, whereby spins are pumped from a magnet into the adjacent target material under the ferromagnetic resonance condition. We theoretically investigate the spin…

Mesoscale and Nanoscale Physics · Physics 2020-05-14 Yusei Fujimoto , Masanori Ichioka , Hiroto Adachi

We investigate charge and spin transport through an adiabatically driven, strongly interacting quantum dot weakly coupled to two metallic contacts with finite bias voltage. Within a kinetic equation approach, we identify coefficients of…

Mesoscale and Nanoscale Physics · Physics 2015-06-11 Hernan L. Calvo , Laura Classen , Janine Splettstoesser , Maarten R. Wegewijs

We demonstrate the operation of a quantum spin pump based on cyclic radio-frequency excitation of a GaAs quantum dot, including the ability to pump pure spin without pumping charge. The device takes advantage of bidirectional mesoscopic…

Mesoscale and Nanoscale Physics · Physics 2012-11-19 Susan K. Watson , R. M. Potok , C. M. Marcus , V. Umansky

Spin pumping and spin-transfer torques are two reciprocal phenomena widely studied in ferromagnetic materials. However, pumping from antiferromagnets and its relation to current-induced torques have not been explored. By calculating how…

Mesoscale and Nanoscale Physics · Physics 2014-08-04 Ran Cheng , Jiang Xiao , Qian Niu , Arne Brataas