A theory of spin relaxation in graphene including intrinsic, Bychkov-Rashba, and ripple spinorbit coupling is presented. We find from spin relaxation data by Tombros et al. (Nature, 448 (2007) 571) that intrinsic spin-orbit coupling dominates over other contributions with a coupling constant of 3.7 meV. Although it is 1–3 orders of magnitude larger than those obtained from first principles, we ...

We discuss the precession of spin-polarized ultracold neutrons UCNs and He atoms in uniform and static magnetic and electric fields and calculate the spin relaxation effects from motional v E magnetic fields. Particle motion in an electric field creates a motional v E magnetic field, which when combined with collisions produces variations of the total magnetic field and results in spin relaxati...

We have, using spin-echo nuclear magnetic resonance spectroscopy, measured the relaxation times and diffusion coefficient of water protons in primary mammary adenocarcinomas of mice. In our biological model, three morphological stages were defined: (a) mammary gland tissue from pregnant mice, (b) preneoplastic nodules, and (c) neoplastic tissue. It was found that neoplastic tissues could be dis...

The weakly bending rod (WBR) model of double-stranded DNA (dsDNA) is adapted to analyze the internal dynamics of dsDNA as observed in electron paramagnetic resonance (EPR) measurements of the spin-lattice relaxation rate, R(1e), for spin probes rigidly attached to nucleic acid-bases. The WBR theory developed in this work models dsDNA base-pairs as diffusing rigid cylindrical discs connected by ...

1. Introduction We have used the formalism of fictituous spin 1/2 to describe the nuclear relaxation of spins I>l/2 in solids (1). We found a generalized macroscopic kinetic differential equation for any observable, expanded in a complete basis set of independent fictitious spin 1/2 operators, and whose time evolution is expressed in terms of a matrix of relaxation. The interest of such method ...

Concentrated Aqueous Protein Systems, Proton Relaxation Times, Slow Chemical Exchange In this paper we present proton spin-lattice (T1) and spin-spin (T2) relaxation times measured vs. concentration, temperature, pulse interval (tauCPMG) as well as 1H NMR spectral measurements in a wide range of concentrations of bovine serum albumin (BSA) solutions. The anomalous relaxation behaviour of the wa...

Recent and ongoing optical experiments on mechanisms and methods for control and gating of spin relaxation in semiconductor quantum wells are reviewed. We discuss work on high-mobility two-dimensional electron gases in (001)-grown GaAs/AlGaAs wells which reveals two new aspects of D’yakonov, Perel’ and Kachorovskii (DPK) spin dynamics, namely oscillatory spin evolution in a quasi-collision-free...

We determine the spin-lifetime anisotropy of spin-polarized carriers in graphene. In contrast to prior approaches, our method does not require large out-of-plane magnetic fields and thus it is reliable for both low- and high-carrier densities. We first determine the in-plane spin lifetime by conventional spin precession measurements with magnetic fields perpendicular to the graphene plane. Then...

We report time resolved measurements of spin and carrier relaxation in InAs films with carrier densities of 1.3 1016 and 1.6 1016 cm−3 grown on 001 and 111 GaAs, respectively. We used standard pump-probe and magneto-optical Kerr effect spectroscopy at different excitation wavelengths, power densities, and temperatures. We observed sensitivity of carrier and spin relaxation time to the photoindu...

A model-free theoretical framework for a phenomenological description of spin-lattice relaxation by anomalous translational diffusion in inhomogeneous systems based on the fractional diffusion equation is developed. The dependence of the spin-lattice relaxation time on the size of the pores in porous glass Vycor is experimentally obtained and found to agree well with our theoretical predictions...