Decoherence and purity of a driven solid-state qubit in Ohmic bath

TL;DR

This paper analyzes how a driven solid-state qubit's decoherence and purity are affected by an Ohmic bath, revealing the critical role of certain coefficients and the influence of driving field parameters on decoherence time.

Contribution

It introduces a novel analysis focusing on the coefficients of the master equation, highlighting the impact of driven field parameters on qubit decoherence and purity.

Findings

Decoherence coefficient is crucial for qubit decoherence.

Decoherence time decreases with higher driven field amplitude.

Decoherence time increases with higher driven field frequency.

Abstract

In this paper we study the decoherence and purity of a driven solid-state qubit in the Ohmic bath by using the method based on the master equation. At first, instead of solving the master equation we investigate the coefficients of the equation which describe the shift in frequency, diffusive, decoherence, and so on. It is shown that one of the coefficients (we called it decoherence coefficient) is crucial to the decoherence of the qubit in the model. Then we investigate the evolution of the purity of the state in the model. From the analysis of the purity we see that the decoherence time of the qubit decrease with the increase of the amplitude of the driven fields and it is increase with the increase of the frequency of the driven fields.