# Quantum dynamical speedup in correlated noisy channels

## TL;DR

This paper explores how correlations in noisy quantum channels can be manipulated to accelerate the evolution speed of a two-qubit system, revealing channel-dependent effects on quantum speed limits.

## Contribution

It introduces a method to accelerate quantum evolution by adjusting channel correlations and initial entanglement, with distinct effects across different noise channels.

## Key findings

- QSLT can be shortened by increasing channel correlation and entanglement in amplitude damping and depolarizing channels.
- Phase damping channel shows contrasting behavior with no speedup from increased correlation.
- Transition from no-speedup to speedup evolution is controllable via channel correlation in depolarizing channels.

## Abstract

The maximal evolution speed of a quantum system can be represented by quantum speed limit time (QSLT).We investigate QSLT of a two-qubit system passing through a correlated channel (amplitude damping, phase damping, and depolarizing).By adjusting the correlation parameter of channel and the initial entanglement,a method to accelerate the evolution speed of the system for some specific channels is proposed.It is shown that, in amplitude damping channel and depolarizing channel,QSLT may be shortened in some cases by increasing correlation parameter of the channel and initial entanglement, which are in sharp contrast to phase damping channel.In particular, under depolarizing channels, the transition from no-speedup evolution to speedup evolution for the system can be realized by changing correlation strength of the channel.