J. L. Cheng

Anisotropic spin transport in GaAs quantum wells in the presence of competing Dresselhaus and rashba spin-orbit coupling

Aiming at the optimization of the spin-diffusion length in (001) GaAs quantum wells, we explore the effect of the anisotropy of the spin-orbit coupling on the competition between the Rashba and the Dresselhaus spin-orbit couplings by solving the kinetic spin Bloch equations with the electron-phonon and the electron-electron scattering explicitly included. For identical strengths of the Rashba and the Dresselhaus spin-orbit couplings, the spin-diffusion length shows strong anisotropy not only for the spin-polarization direction but also for the spin-diffusion direction. Two special directions are used seeking for the large diffusion length:

Hole spin relaxation in semiconductor quantum dots

(\overline{1}10)

Spin relaxation in GaAs quantum dots

and (110). Without the cubic term of the Dresselhaus spin-orbit coupling and with the identical Dresselhaus and Rashba strengths, infinite diffusion lengths can be obtained either for the spin-diffusion∕injection direction along

Intense terahertz laser fields on a two-dimensional electron gas with Rashba spin–orbit coupling

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Spin diffusion/transport in n-type GaAs quantum wells

, regardless of the direction of spin polarization, or for the spin polarization along (110), regardless of the direction of the spin diffusion∕injection. However, the cubic Dresselhaus term cannot be neglected, resulting in a finite spin-diffusion length which decreases with the temperature and the electron density. The anisotropy for the spin-diffusion direction and spin-polarization direction is maintained. For the spin-diffusion∕injection direction along

Spin relaxation under identical Dresselhaus and Rashba coupling strengths in GaAs quantum wells

(\overline{1}10)

Red-shift of vanadate band-gap by cation substitution for application in phosphor-converted white light-emitting diodes

, the spin-diffusion length increases first with the increase of the Rashba strength (from 0) which can be tuned by the external gate voltage; when the Rashba strength is slightly smaller than (instead of equal to) the Dresselhaus strength, the diffusion length reaches its maximum, followed by a decrease with further increase of the Rashba strength.

Diffusion and transport of spin pulses in an n-type semiconductor quantum well

Hole spin relaxation time due to the hole--acoustic-phonon scattering in

Full band structure calculation of two-photon indirect absorption in bulk silicon

\mathrm{GaAs}

Crystal-field analyses for trivalent lanthanide ions in LiYF4

quantum dots confined in quantum wells along (001) and (111) directions is studied after the exact diagonalization of Luttinger Hamiltonian. Different effects such as strain, magnetic field, quantum dot diameter, quantum well width, and the temperature on the spin relaxation time are investigated thoroughly. Many features that are quite different from the electron spin relaxation in quantum dots and quantum wells are presented with the underlying physics elaborated.