Binary Optimal Control Of Single-Flux-Quantum Pulse Sequences
- URL: http://arxiv.org/abs/2106.10329v3
- Date: Tue, 23 Aug 2022 06:49:23 GMT
- Title: Binary Optimal Control Of Single-Flux-Quantum Pulse Sequences
- Authors: Ryan H. Vogt, N. Anders Petersson
- Abstract summary: We introduce a binary, relaxed gradient, trust-region method for optimizing pulse sequences for single flux quanta (SFQ) control of a quantum computer.
We present numerical results for the H and X gates, where the optimized pulse sequences give gate fidelity's better than $99.9%$, in $approx 25$ trust-region.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We introduce a binary, relaxed gradient, trust-region method for optimizing
pulse sequences for single flux quanta (SFQ) control of a quantum computer. The
pulse sequences are optimized with the goal of realizing unitary gate
transformations. Each pulse has a fixed amplitude and duration. We model this
process as an binary optimal control problem, constrained by Schr\"{o}dinger's
equation, where the binary variables indicate whether each pulse is on or off.
We introduce a first-order trust-region method, which takes advantage of a
relaxed gradient to determine an optimal pulse sequence that minimizes the gate
infidelity, while also suppressing leakage to higher energy levels. The
proposed algorithm has a computational complexity of ${\cal O}(p\log(p)$, where
$p$ is the number of pulses in the sequence. We present numerical results for
the H and X gates, where the optimized pulse sequences give gate fidelity's
better than $99.9\%$, in $\approx 25$ trust-region iterations.
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