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arXiv · 2607.16124

Reverse engineering of single-qubit quantum gates

Gustavo Fernandes da Costa·Leonardo K. Castelano·Emanuel Fernandes de Lima
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Abstract

In this work, we address the problem of designing single-qubit quantum gates by means of a linearly-polarized field. We show that any desired one-qubit gate corresponding to a special unitary matrix can be generated by a modulated sinusoidal field. The only approximation involved is the rotating-wave-approximation. The formula for the control field is obtained by inverting the equation of motion for the evolution operator and imposing the conditions for the desired gate. We give a simple procedure to obtain closed analytical formulas for the fields in terms of a priori chosen dynamical functions. Additionally, these dynamical functions can depend on tunable free parameters intentionally introduced to meet a desired performance criteria.

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Gustavo Fernandes da Costa, Leonardo K. Castelano, Emanuel Fernandes de Lima. 2026-07-17. Reverse engineering of single-qubit quantum gates. https://arxiv.org/abs/2607.16124

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