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Quantum control using quantum memory.

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.

SUBMITTER: Roget M

PROVIDER: S-EPMC7721887 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Quantum control using quantum memory.

Roget Mathieu M Herzog Basile B Di Molfetta Giuseppe G

Scientific reports 20201207 1

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 significant ...[more]

PMID: 33288805

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