Continuous weak measurement and feedback control of a solid-state charge qubit: physical unravelling of non-Lindblad master equation

TL;DR

This paper introduces a physical unravelling scheme for a non-Lindblad master equation in the context of continuous measurement and feedback control of a solid-state charge qubit, demonstrating self-consistency and numerical efficiency.

Contribution

It extends quantum trajectory theory to non-Lindblad equations for solid-state qubits, enabling better modeling of measurement and control processes.

Findings

Control effect observed in detector noise spectrum

Measurement voltage impact analyzed

Scheme shows good numerical efficiency

Abstract

Conventional quantum trajectory theory developed in quantum optics is largely based on the physical unravelling of Lindbald-type master equation, which constitutes the theoretical basis of continuous quantum measurement and feedback control. In this work, in the context of continuous quantum measurement and feedback control of a solid-state charge qubit, we present a physical unravelling scheme of non-Lindblad type master equation. Self-consistency and numerical efficiency are well demonstrated. In particular, the control effect is manifested in the detector noise spectrum, and the effect of measurement voltage is discussed.