Quantum control using quantum memory

TL;DR

This paper introduces a quantum control scheme using quantum memory to precisely manipulate a quantum walk's trajectory and variance, enabling advanced quantum simulations on future quantum devices.

Contribution

It presents a novel quantum control method that encodes desired dynamics in the initial state, facilitating exact control of quantum walks in two-dimensional space-time.

Findings

Analytical encoding of arbitrary walker's mean trajectory and variance.

Potential for implementing complex physics models on quantum devices.

Advances in simulating quantum field theories on curved manifolds.

Abstract

We propose a new quantum numerical scheme to control the dynamics of a quantum walker in a two dimensional space-time grid. More specifically, we show how, introducing a quantum memory for each of the spatial grid, this result can be achieved simply by acting on the initial state of the whole system, and therefore can be exactly controlled once for all. As example we prove analytically how to encode in the initial state any arbitrary walker's mean trajectory and variance. This brings significantly closer the possibility of implementing dynamically interesting physics models on medium term quantum devices, and introduces a new direction in simulating aspects of quantum field theories (QFTs), notably on curved manifold.