Fundamental Speed Limits on Quantum Coherence and Correlation Decay

TL;DR

This paper establishes universal speed limits on how quickly quantum coherence and correlations can decay, which are crucial for understanding decoherence in quantum systems and their implications for quantum technologies.

Contribution

It introduces fundamental bounds on the rates of quantum coherence and correlation decay, revealing universal constraints in quantum dephasing processes.

Findings

Universal relationships constrain dephasing rates

Speed limits become significant in multi-partite systems

Quantum correlations cannot decay arbitrarily fast

Abstract

The study and control of coherence in quantum systems is one of the most exciting recent developments in physics. Quantum coherence plays a crucial role in emerging quantum technologies as well as fundamental experiments. A major obstacle to the utilization of quantum effects is decoherence, primarily in the form of dephasing that destroys quantum coherence, and leads to effective classical behaviour. We show that there are universal relationships governing dephasing, which constrain the relative rates at which quantum correlations can disappear. These effectively lead to speed limits which become especially important in multi-partite systems.