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arXiv · 2106.09148

Quantum Optimal Control for Pure-State Preparation Using One Initial State

Stefanie Günther·N. Anders Petersson·Jonathan L. DuBois
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Abstract

This paper presents a framework for solving the pure-state preparation problem using numerical optimal control. As an example, we consider the case where a number of qubits are dispersively coupled to a readout cavity. We model open system quantum dynamics using the Markovian Lindblad master equation, driven by external control pulses. The main result of this paper develops a basis of density matrices (a parameterization) where each basis element is a density matrix itself. Utilizing a specific objective function, we show how an ensemble of the basis elements can be used as a single initial state throughout the optimization process - independent of the system dimension. We apply the general framework to the specific application of ground-state reset of one and two qubits coupled to a readout cavity.

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Stefanie Günther, N. Anders Petersson, Jonathan L. DuBois. 2021-06-16. Quantum Optimal Control for Pure-State Preparation Using One Initial State. https://doi.org/10.1116/5.0060262

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