Spin-phonon decoherence in solid-state paramagnetic defects from first principles

Decoherence and Dynamical Decoupling in Solid-state Spin Qubits

Title of dissertation: DECOHERENCE AND DYNAMICAL DECOUPLING IN SOLID-STATE SPIN QUBITS Wayne Martin Witzel Doctor of Philosophy, 2007 Dissertation directed by: Professor Sankar Das Sarma Department of Physics This dissertation is a study of the decoherence of a solid-state spin qubit, either that of a localized electron spin or a donor nucleus, caused by a nuclear spin bath relevant to semicond...

Role of N defects in paramagnetic CrN at finite temperatures from first principles

Simulations of defects in paramagnetic materials at high temperature constitute a formidable challenge to solid-state theory due to the interaction of magnetic disorder, vibrations, and structural relaxations. CrN is a material where these effects are particularly large due to a strong magnetolattice coupling and a tendency for deviations from the nominal 1:1 stoichiometry. In this work, we pre...

Decoherence in Solid State Qubits

Interaction of solid state qubits with environmental degrees of freedom strongly affects the qubit dynamics, and leads to decoherence. In quantum information processing with solid state qubits, decoherence significantly limits the performances of such devices. Therefore, it is necessary to fully understand the mechanisms that lead to decoherence. In this review we discuss how decoherence affect...

Phonon thermal transport in Bi2Te3 from first principles

Phonon-assisted optical absorption in silicon from first principles.

The phonon-assisted interband optical absorption spectrum of silicon is calculated at the quasiparticle level entirely from first principles. We make use of the Wannier interpolation formalism to determine the quasiparticle energies, as well as the optical transition and electron-phonon coupling matrix elements, on fine grids in the Brillouin zone. The calculated spectrum near the onset of indi...