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Related papers: Spin Bias Measurement Based on a Quantum Point Con…

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We study the interaction between two adjacent but electrically isolated quantum point contacts (QPCs). At high enough source-drain bias on one QPC, the drive QPC, we detect a finite electric current in the second, unbiased, detector QPC.…

Mesoscale and Nanoscale Physics · Physics 2007-09-03 V. S. Khrapai , S. Ludwig , J. P. Kotthaus , H. P. Tranitz , W. Wegscheider

Spin and charge transport through a quantum dot coupled to external nonmagnetic leads is analyzed theoretically in terms of the non-equilibrium Green function formalism based on the equation of motion method. The dot is assumed to be…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 R. Swirkowicz , J. Barnas , M. Wilczynski

We propose a novel scheme to efficiently polarize and manipulate the electron spin in a quantum dot. This scheme is based on the spin-orbit interaction and it possesses following advantages: (1) The direction and the strength of the spin…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Qing-feng Sun , X. C. Xie

We demonstrate that the combination of an external magnetic field and the intrinsic spin-orbit interaction results in nonadiabatic precession of the electron spin after transmission through a quantum point contact (QPC). We suggest that…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 T. Li , O. P. Sushkov

We propose a new device to create a tunable all-electric spin polarizer: a quantum point contact (QPC) with four gates -- two in-plane side gates in series. The first pair of gates, near the source, is asymmetrically biased to create spin…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 J. Charles , N. Bhandari , J. Wan , M. Cahay , R. S. Newrock

We show that the coherent mixing of different transverse modes, due to forward scattering of carriers by soft impurity- or boundary potentials leads to a nonlinear, asymmetric current response of quantum point contacts (QPC). The…

Condensed Matter · Physics 2009-10-22 A. M. Zagoskin , R. I. Shekhter

We report the observation of an anomalous conductance plateau near G = 0.5 G0 (G0 = 2e2/h) in asymmetrically biased AlGaAs/GaAs quantum point contacts (QPCs), with in-plane side gates in the presence of lateral spin-orbit coupling. This is…

Mesoscale and Nanoscale Physics · Physics 2012-04-24 N. Bhandari , P. P. Das , M. Cahay , R. S. Newrock , S. T. Herbert

We report measurements of spin transitions for GaAs quantum dots in the Coulomb blockade regime, and compare ground and excited state transport spectroscopy to direct measurements of the spin polarization of emitted current. Transport…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 R. M. Potok , J. A. Folk , C. M. Marcus , V. Umansky , M. Hanson , A. C. Gossard

Nuclear spin polarization is typically generated in GaAs quantum point contacts (QPCs) when an out-of-plane magnetic field gives rise to spin-polarized quantum Hall edge states, and a voltage bias drives transitions between the edge states…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 Y. Ren , W. Yu , S. M. Frolov , J. A. Folk , W. Wegscheider

We report a study of spin dependent transport in a system composed of a quantum dot coupled to a normal metal lead and a ferromagnetic lead (NM-QD-FM). We use the master equation approach to calculate the spin-resolved currents in the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 F. M. Souza , J. C. Egues , A. P. Jauho

We report an electronic magnetization measurement of a quantum point contact (QPC) based on nuclear magnetic resonance (NMR) spectroscopy. We find that NMR signals can be detected by measuring the QPC conductance under in-plane magnetic…

Mesoscale and Nanoscale Physics · Physics 2015-07-16 Minoru Kawamura , Keiji Ono , Peter Stano , Kimitoshi Kono , Tomosuke Aono

We report electronic control and measurement of an imbalance between spin-up and spin-down electrons in micron-scale open quantum dots. Spin injection and detection was achieved with quantum point contacts tuned to have spin-selective…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 E. J. Koop , B. J. van Wees , D. Reuter , A. D. Wieck , C. H. van der Wal

Adiabatically pumped charge, carried by non-interacting electrons through a quantum dot in a turnstile geometry, is studied as function of the strength of the two modulating potentials (related to the conductances of the two point-contacts…

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

Spin and charge currents can be generated by an ac voltage through a one-channel quantum wire with strong electron interactions in a static uniform magnetic field. In a certain range of low voltages, the spin current can grow as a negative…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Bernd Braunecker , D. E. Feldman

We develop a theoretical description of transport through quantum dots connected to reservoirs via spin-polarized ballistic contacts. Rate equations account for spin accumulation inside the dot, electron-electron interactions, and…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Eugene G. Mishchenko , Arne Brataas , Yaroslav Tserkovnyak

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 implement a microscopic spin filter for cold fermionic atoms in a quantum point contact (QPC) and create fully spin-polarized currents while retaining conductance quantization. Key to our scheme is a near-resonant optical tweezer…

The conversion of spin information into electrical signals is indispensable for spintronic technologies. Spin-to-charge conversion in ferromagnetic tunnel contacts is well-described using linear (spin-)transport equations, provided that…

Mesoscale and Nanoscale Physics · Physics 2018-10-29 R. Jansen , A. Spiesser , H. Saito , Y. Fujita , S. Yamada , K. Hamaya , S. Yuasa

We present a theoretical analysis of the nonlinear bias and temperature dependence of current-voltage characteristics of a spin-valve device which is formed by connecting a quantum dot to two ferromagnetic electrodes whose magnetic moments…

Condensed Matter · Physics 2015-06-25 Baigeng Wang , Jian Wang , Hong Guo

A non-equilibrium Green function formalism (NEGF) is used to study the conductance of a side-gated quantum point contact (QPC) in the presence of lateral spin-orbit coupling (LSOC). A small difference of bias voltage between the two side…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 J. Wan , M. Cahay , P. Debray , R. Newrock