vix.ing · top · new · best · stats · spec

Long-time coherence in fourth-order spin correlation functions

2017/05/31 by Nina Fröhling, Frithjof B. Anders
Mathematics · Physics and Astronomy · #Atomic and Subatomic Physics Research #Coherence (philosophical gambling strategy) #Correlation #Geometry #Mathematics #Order (exchange) #Physics #Quantum and electron transport phenomena #Quantum mechanics #Quantum optics and atomic interactions #Spin (aerodynamics) #Statistical physics #cond-mat.mes-hall

paper · pdf · doi:10.1103/physrevb.96.045441

13 pages, 9 figures

openalex publication_date 2017/07/31 · arxiv created 2017/10/20 · arxiv updated 2017/10/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We study the long-time decay of fourth-order electron spin correlation functions for an isolated singly charged semiconductor quantum dot. The electron spin dynamics is governed by the applied external magnetic field as well as the hyperfine interaction. While the long-time coherent oscillations in the correlation functions can be understood within a semiclassical approach treating the Overhauser field as frozen, the field dependent decay of its amplitude reported in different experiments cannot be explained by the central-spin model indicating the insufficiency of such a description. By incorporating the nuclear Zeeman splitting and the strain induced nuclear-electric quadrupolar interaction, we find the correct crossover from a fast decay in small magnetic fields to a slow exponential asymptotic in large magnetic fields. It originates from a competition between the quadrupolar interaction inducing an enhanced spin decay and the nuclear Zeeman term that suppressed the spin-flip processes. We are able to explain the magnetic field dependency of the characteristic long-time decay time T2 depending on the experimental setups. The calculated asymptotic values of T2=3--4\phantom\rule0.16em0ex\ensuremathμs agree qualitatively well with the experimental data.

Citations