Stronger Quantum Speed Limit For Mixed Quantum States

TL;DR

This paper introduces an improved quantum speed limit for mixed states, leveraging a stronger uncertainty relation and optimization over operators, demonstrating superior bounds compared to previous results.

Contribution

It develops a new quantum speed limit for mixed states using a stronger uncertainty relation and operator optimization, enhancing previous bounds.

Findings

The new bound outperforms earlier bounds in examples.

Optimization over operators improves the tightness of the bound.

The approach applies to unitary evolution of mixed states.

Abstract

We derive a quantum speed limit for mixed quantum states using the stronger uncertainty relation for mixed quantum states and unitary evolution. We also show that this bound can be optimized over different choices of operators for obtaining a better bound. We illustrate this bound with some examples and show its better performance with respect to some earlier bounds.