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A Quantum-Dot Array as Model for Copper-Oxide Superconductors: A Dedicated Quantum Simulator for the Many-Fermion Problem

Efstratios Manousakis
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Abstract

Quantum systems with a large number of fermionic degrees of freedom are intractable by quantum simulations. In this paper we introduce the concept of a dedicated quantum simulator(DQS) which is an artificial system of quantum dots whose Hamiltonian maps exactly to the original many fermion problem. While the universal quantum simulator (UQS) introduced by Feynman in 1982 can simulate any quantum mechanical many-body problem, a DQS can only solve a particular many body problem. Our concept of the dedicated quantum simulator is not a quantum computer but rather a quantum "analog" device, dedicated to a particular quantum computation. As an example, we consider the system of the $CuO$ plane in the copper-oxide superconductors and we propose an array of electrostatically confined quantum dots to be used as its dedicated quantum simulator. We show that this dedicated device can be used to image stripe formation as a function of the electron doping using electric force microscopy. We argue that such a dedicated quantum simulator may be easier to realize in the future compared to a general purpose quantum computer.

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Efstratios Manousakis. 2002-01-09. A Quantum-Dot Array as Model for Copper-Oxide Superconductors: A Dedicated Quantum Simulator for the Many-Fermion Problem. https://arxiv.org/abs/cond-mat/0201142

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