English
Related papers

Related papers: Electron Number Dependence of Spin Triplet-Singlet…

200 papers

We present a detailed experimental and theoretical analysis of the spin dynamics of two-dimensional electron gases (2DEGs) in a series of n-doped GaAs/AlGaAs quantum wells. Picosecond-resolution polarized pump-probe reflection techniques…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 W. J. H. Leyland , G. H. John , R. T. Harley , M. M. Glazov , E. L. Ivchenko , D. A. Ritchie , A. J. Shields , M. Henini

We calculate that the electron states of strained self-assembled Ge/Si quantum dots provide a convenient two-state system for electrical control. An electronic state localized at the apex of the quantum dot is nearly degenerate with a state…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 C. E. Pryor , M. E. Flatté , J. Levy

We report a surprisingly long spin relaxation time of electrons in Mn-doped p-GaAs. The spin relaxation time scales with the optical pumping and increases from 12 ns in the dark to 160 ns upon saturation. This behavior is associated with…

Spin properties of single electron states in laterally coupled quantum dots in the presence of a perpendicular magnetic field are studied by exact numerical diagonalization. Dresselhaus (linear and cubic) and Bychkov-Rashba spin-orbit…

Other Condensed Matter · Physics 2007-05-23 Peter Stano , Jaroslav Fabian

We engineer a system of two strongly confined quantum dots to gain reproducible electrostatic control of the spin at zero magnetic field. Coupling the dots in a tight ring-shaped potential with two tunnel barriers, we demonstrate that an…

A nanodevice capable of separating spins of two electrons confined in a quantum dot formed in a gated semiconductor nanowire is proposed. Two electrons confined initially in a single quantum dot in the singlet state are transformed into the…

Mesoscale and Nanoscale Physics · Physics 2014-02-25 J. Pawłowski , P. Szumniak , A. Skubis , S. Bednarek

We consider two interacting electrons in a semiconductor quantum dot structure which consists of a small dot within a larger dot, and demonstrate a singlet-triplet filtering mechanism which involves spin-dependent resonances and can…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 G. Giavaras , J. H. Jefferson , M. Fearn , C. J. Lambert

We present a theoretical analysis of the phonon-assisted relaxation in a system composed of two self-assembled vertically stacked quantum dots. We construct realistic model, which takes into account the geometry and strain distribution in…

Mesoscale and Nanoscale Physics · Physics 2013-01-16 Krzysztof Gawarecki , Paweł Machnikowski

The magnetic field dependence of the electronic properties of \textit{real} single vertical quantum dots in circular and rectangular mesas is investigated within a full three-dimensional multiscale self-consistent approach without any {\it…

The relaxation process of electron spin in systems of electrons interacting with piezoelectric deformation phonons that are mediated through spin-orbit interactions was interpreted from a microscopic point of view using the formula for the…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 Nam Lyong Kang

The electron spin relaxation times in a system of electrons interacting with piezoelectric phonons mediated through spin-orbit interactions were calculated using the formula derived from the projection-reduction method. The results showed…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 Nam Lyong Kang

We develop a theoretical model to describe the dissipative dynamics of singlet-triplet qubits in GaAs quantum dots. Using the concurrence experimentally obtained [M. D. Shulman et al., Science 336, 202 (2012)] as a guide, we found that each…

Quantum Physics · Physics 2017-01-13 L. K. Castelano , F. F. Fanchini , K. Berrada

Quantum limits of power dissipation in spintronic computing are estimated. A computing element composed of a single electron in a quantum dot is considered. Dynamics of its spin due to external magnetic field and interaction with adjacent…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Dmitri E. Nikonov , George I. Bourianoff , Paolo Gargini

We study decoherence of an electron spin qubit in a quantum dot due to charge noise. We find that at the lowest order, the pure dephasing channel is suppressed for both $1/f$ charge noise and Johnson noise, so that charge noise leads to a…

Mesoscale and Nanoscale Physics · Physics 2014-05-23 Peihao Huang , Xuedong Hu

The electron spin relaxation in $n$-type and intrinsic GaAs$_{1-x}$Bi$_x$ with Bi composition $0\le x \le 0.1$ is investigated from the microscopic kinetic spin Bloch equation approach. The incorporation of Bi is shown to markedly decrease…

Materials Science · Physics 2012-09-19 H. Tong , X. Marie , M. W. Wu

We have investigated spin relaxation times in CdTe quantum dots doped with a single Mn atom, a prototype of a system where the interaction between a single charge carrier and a single spin takes place. A theoretical model that was used…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 Marko D. Petrović , Nenad Vukmirović

Spin relaxation under identical Dresselhaus and Rashba coupling strengths in GaAs quantum wells is studied in both the traditional collinear statistics, where the energy spectra do not contain the spin-orbit coupling terms, and the helix…

Materials Science · Physics 2007-05-23 J. L. Cheng , M. W. Wu

We consider a single electron in a 1D quantum dot with a static slanting Zeeman field. By combining the spin and orbital degrees of freedom of the electron, an effective quantum two-level (qubit) system is defined. This pseudo-spin can be…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Yasuhiro Tokura , Wilfred G. van der Wiel , Toshiaki Obata , Seigo Tarucha

We investigate the Kondo effect in a quantum dot with almost degenerate spin-singlet and triplet states for an even number of electrons. We show that the Kondo temperature as a function of the energy difference between the states Delta…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Mikio Eto , Yuli V. Nazarov

Due to the spin-orbital coupling in a semiconductor quantum dot, a freely precessing electron spin produces a time-dependent charge density. This creates a sizeable electric field outside the dot, leading to promising applications in…

Mesoscale and Nanoscale Physics · Physics 2008-04-12 L. S. Levitov , E. I. Rashba