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arXiv · 2305.03261

Direct Collocation for Quantum Optimal Control

Aaron Trowbridge·Aditya Bhardwaj·Kevin He·David I. Schuster·Zachary Manchester
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Abstract

We present an adaptation of direct collocation -- a trajectory optimization method commonly used in robotics and aerospace applications -- to quantum optimal control (QOC); we refer to this method as Pade Integrator COllocation (PICO). This approach supports general nonlinear constraints on the states and controls, takes advantage of state-of-the-art large-scale nonlinear programming solvers, and has superior convergence properties compared to standard approaches like GRAPE and CRAB. PICO also allows for the formulation of novel free-time and minimum-time control problems -- crucial for realizing high-performance quantum computers when the optimal pulse duration is not known a priori. We demonstrate PICO's performance both in simulation and on hardware with a 3D circuit cavity quantum electrodynamics system.

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Aaron Trowbridge, Aditya Bhardwaj, Kevin He, David I. Schuster, Zachary Manchester. 2023-05-05. Direct Collocation for Quantum Optimal Control. https://arxiv.org/abs/2305.03261

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