Electron Spin as a Spectrometer of Nuclear-Spin Noise and Other Fluctuations

Abstract

AbstractThis chapter establishes the relationship between low-frequency noise and coherence decay of localized spins in semiconductors, as measured by a number of different pulse spin resonance sequences. A general relationship between an arbitrary noise spectral function and spin phase relaxation is derived, allowing microscopic calculations of electron spin-echo decay due to the magnetic noise produced by interacting nuclear spins. The electron–nuclear spin Hamiltonian is reviewed, including isotropic and anisotropic hyperfine interactions, internuclear dipolar interactions, and the effective nuclear–nuclear coupling mediated by the electron-spin hyperfine interaction. A microscopic calculation of the nuclear-spin noise spectrum arising due to nuclear–nuclear dipolar flip-flops is presented. We compare our explicit numerical results to electron spin-echo decay experiments of phosphorus impurities embedded in natural and in nuclear-spin-enriched silicon.KeywordsElectron SpinNoise SpectrumFree Induction DecayMagnetic NoiseSpin CoherenceThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.