Electron spin relaxation of transition metal ions with spin S> or =1 results primarily from thermal modulation of the zero field splitting (zfs) tensor. This occurs both by distortion of the zfs tensor due to intermolecular collisions and, for complexes with less than cubic symmetry, by reorientational modulation of the permanent zfs tensor. The reorientational mechanism is much less well chara...

We study relaxation of a moving spin qubit caused by phonon noise. As we vary the speed of the qubit, we observe several interesting features in spin relaxation and the associated phonon emission, induced by Doppler effect. In particular, in the supersonic regime, the phonons emitted by the relaxing qubit is concentrated along certain directions, similar to the shock waves produced in classical...

Spin relaxation in a microscopic model of spin maser is studied theoretically. Seven qualitatively different regimes are found: free induction, collective induction, free relaxation, collective relaxation, weak superradiance, pure superradiance, and triggered superradi-ance. The initiation of relaxation can be originated either by an imposed initial coherence or by local spin fluctuations due t...

We investigate the singlet-triplet relaxation process of a two electron silicon quantum dot. In the absence of a perpendicular magnetic field, we find that spin-orbit coupling is not the main source of singlet-triplet relaxation. Relaxation in this regime occurs mainly via virtual states and is due to nuclear hyperfine coupling. In the presence of an external magnetic field perpendicular to the...

We investigate the spin dynamics and relaxation in remotely doped two dimensional electron systems where the dopants lead to random fluctuations of the Rashba spin-orbit coupling. Due to the resulting random-spin precession, the spin-relaxation time is limited by the strength and spatial scale of the random contribution to the spin-orbit coupling. We concentrate on the role of the randomness fo...

Proton NMR relaxation times T1 and T2 were determined for normal lenses excised from sexually mature animals from seven different species. Lenses were immersed in physiological buffer during measurements, and suppression methods were employed to null the buffer signal. This enabled selective analysis of lenticular water. Observed relaxation times were correlated with protein and water content. ...

The spin and optical polarization based on a coupled InGaN/GaN quantum well (QW) and quantum dots (QDs) structure is investigated. In this structure, spin-electrons can be temporarily stored in QW, and spin injection from the QW into QDs via spin-conserved tunneling is enabled. Spin relaxation can be suppressed owing to the small energy difference between the initial state in the QW and the fin...

A fully microscopic theory of electron spin relaxation by the D’yakonov-Perel’ type spin-orbit coupling is developed for a semiconductor quantum well in an ambient magnetic field applied perpendicular to the plane of the well. We derive Bloch equations for an electron spin in the well and determine explicit microscopic expressions for the spin relaxation times. The dependencies of the electron ...

Recent consideration of spin based quantum computation, optical switches, magnetic memory cells, etc. [1] mandates an improved understanding of spin dynamics and, in particular, the spin relaxation rate [2]. The most promising materials for device purposes, III-V and II-VI compounds, have been shown [3] to have spin relaxation rates dominated by the D’yakonov-Perel’ (DP) mechanism at moderate t...

The potential of reduction of power consumption and the growth of computational speed achieved by scaling of semiconductor devices is close to exhaustion. Utilizing spin properties of electrons might provide an opportunity for further improvement of the properties of microelectronic-based devices. Since silicon is the main material currently used in microelectronics, we investigate the properti...