Zeno and anti-Zeno dynamics in spin-bath models

TL;DR

This paper explores how quantum Zeno and anti-Zeno effects influence spin decoherence in spin bath models, revealing the critical role of system-bath coupling and external conditions like temperature and bias.

Contribution

It demonstrates the control of Zeno-anti-Zeno transition by system-bath coupling and analyzes effects of bias, temperature, and magnetic field on decoherence.

Findings

Zeno-anti-Zeno transition is governed by system-bath coupling.

Decoherence rate is affected by electrical bias, temperature, and magnetic field.

Crossover behavior observed in biased, high-temperature, and nonequilibrium systems.

Abstract

We investigate the quantum Zeno and anti-Zeno effects in spin bath models: the spin-boson model and a spin-fermion model. We show that the Zeno-anti-Zeno transition is critically controlled by the system-bath coupling parameter, the same parameter that determines spin decoherence rate. We also discuss the crossover in a biased system, at high temperatures, and for a nonequilibrium spin-fermion system, manifesting the counteracting roles of electrical bias, temperature, and magnetic field on the spin decoherence rate.