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DOE OSTI · 3378006

Trajectory-independent speed limits for controlled open quantum systems

Larsen, James B. [Univ. of Michigan, Ann Arbor, MI (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:000000020777440X)·Albash, Tameem [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000339163985)·Magann, Alicia B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000214023487)·Arenz, Christian [Arizona State Univ., Tempe, AZ (United States)] (ORCID:0000000179642468)
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Abstract

Existing quantum speed limits for controlled open quantum systems depend on the specified trajectory. For example, lower bounds on quantum annealing times in the presence of dissipation depend explicitly on the chosen annealing schedule. Recently, schedule-independent speed limits have been derived for annealing in the closed quantum system setting [L. P. García-Pintos et al ., SciPost Phys. 18 , 159 (2025)]. In this work, we generalize these results to open quantum systems, deriving schedule-independent lower bounds for quantum annealing times in systems described by a Lindblad master equation. We analyze the interplay between coherent control and dissipation in single- and two-qubit examples, demonstrating that the derived lower bounds capture key scaling behavior with respect to the strength of the dissipator. Finally, we apply the bound to thermal state preparation and show that the bound matches the expected asymptotic behavior for an Ising model in the high-temperature limit.

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Larsen, James B. [Univ. of Michigan, Ann Arbor, MI (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:000000020777440X), Albash, Tameem [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000339163985), Magann, Alicia B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000214023487), Arenz, Christian [Arizona State Univ., Tempe, AZ (United States)] (ORCID:0000000179642468). 2026-07-16. Trajectory-independent speed limits for controlled open quantum systems. https://doi.org/10.1103/p78c-6p56

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