We present La and Cu NMR relaxation measurements in single crystal La1.67Eu0.2Sr0.13CuO4. A strong peak in the La spin-lattice relaxation rate observed in the spin ordered state is well described by the BPP mechanism @Bloembergen, Purcell, and Pound, Phys. Rev. 73, 679 ~1948!# and arises from continuous slowing of electronic spin fluctuations with decreasing temperature; these spin fluctuations...

Triplet-singlet spin relaxation in a vertical electrostatic quantum dot containing two interacting electrons is studied with a realistic model that includes the effects of finite thickness and screening. The spin relaxation mechanism is taken to be spin mixing via the part of the Dresselhaus Hamiltonian that is linear in the lateral momentum. The electron-electron interaction enhances relaxatio...

We consider spin-lattice relaxation processes for electrons trapped in lateral Si quantum dots in a [001] inversion layer. Such dots are characterized by strong confinement in the direction perpendicular to the surface and much weaker confinement in the lateral direction. The spin relaxation is assumed to be due to the modulation of electron g-factor by the phonon-induced strain, as was shown p...

We have studied theoretically the electron spin relaxation in semiconductor quantum dots via interaction with nuclear spins. The relaxation is shown to be determined by three processes: (i) – the precession of the electron spin in the hyperfine field of the frozen fluctuation of the nuclear spins; (ii) – the precession of the nuclear spins in the hyperfine field of the electron; and (iii) – the...

We demonstrate electrical control of the spin relaxation time T1 between Zeeman-split spin states of a single electron in a lateral quantum dot. We find that relaxation is mediated by the spin-orbit interaction, and by manipulating the orbital states of the dot using gate voltages we vary the relaxation rate W identical withT1(-1) by over an order of magnitude. The dependence of W on orbital co...

The control of spins and spin to charge conversion in organics requires understanding the molecular spin-orbit coupling (SOC), and a means to tune its strength. However, quantifying SOC strengths indirectly through spin relaxation effects has proven difficult due to competing relaxation mechanisms. Here we present a systematic study of the g-tensor shift in molecular semiconductors and link it ...

Silicon is an ideal material for spintronic applications [1] due to long spin lifetime, however, considerable spin relaxation in gated silicon structures was experimentally observed [2]. Surface roughness scattering determines the transport in the channel at high carrier concentration in thin silicon films [3]. Here we investigate the spin relaxation due to surface roughness. The surface roughn...

We investigate phonon-induced spin and charge relaxation mediated by spin-orbit and hyperfine interactions for a single electron confined within a double quantum dot. A simple toy model incorporating both direct decay to the ground state of the double dot and indirect decay via an intermediate excited state yields an electron spin relaxation rate that varies nonmonotonically with the detuning b...

A general theory is developed for describing the nonlinear relaxation of spin systems from a strongly nonequilibrium initial state, when, in addition, the sample is coupled to a resonator. Such processes are characterized by nonlinear stochastic differential equations. This makes these strongly nonequilibrium processes principally different from the spin relaxation close to an equilibrium state...

Nuclear magnetic spin-lattice relaxation in dynamically heterogeneous systems is generally coupled; that is, the rapidly moving liquid components do not relax independently of the rotationally immobilized or solid components. The consequences of this coupling are that the generally observable relaxation rates of the liquid components may not be interpreted using the standard theories of liquid ...