Bath-assisted cooling without resets
Abstract
Cooling an arbitrary mixed state to a pure ground state requires transferring its entropy to an environment. Can a single coherent bath contact accomplish this without repeated bath resets? We develop a new cooling mechanism that transfers the input information into bath degrees of freedom that subsequently decouple, while the system and the remaining bath follow a ground-state path. The bath is discarded only at the end, and the system Hamiltonian remains on and unmodified throughout. We rigorously realize this mechanism for a class of weakly interacting, gapped fermionic systems with local interactions. Starting from any mixed state, our protocol prepares the interacting ground state in total physical time polylogarithmic in the system size and inverse global trace-norm error. It uses two initially empty bath modes per system mode and a single pulse shared across all onsite system--bath couplings. The same pulse prepares each admissible system's own ground state without knowledge of its microscopic parameters. The guarantees follow directly from a non-Markovian system--bath dynamics without an effective Lindbladian description.
Related
- Fluid-layer-assisted mold temperature control for injection-molded bridge-type compliant mechanisms: Experimental thermal validation and simulation-based benchmarking against conventional cooling channels
- Superstrong Dynamics and Directional Emission of a Giant Atom in a Structured Bath
- Nonlinearity-Induced Suppression of Dissipation in Bath-Coupled Floquet Topological Insulators
- Planckian dissipation per unit critical entropy as a coupling-free probe of the strange-metal bath
- Low-field dephasing time of an optically polarized NV- spin bath beyond the P1 limit in diamond: a cluster-correlation-expansion and exact spin-bath study
BibTeX
@misc{yu2026bathassisted,
title = {{Bath-assisted cooling without resets}},
author = {Xie-Hang Yu and Zherui Chen and Lin Lin},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2609.40328},
eprint = {2609.40328},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.40328},
}
RIS
TY - UNPB
TI - Bath-assisted cooling without resets
AU - Xie-Hang Yu
AU - Zherui Chen
AU - Lin Lin
PY - 2026
DA - 2026/10/05
PB - arXiv
DO - 10.48550/arxiv.2609.40328
UR - https://arxiv.org/abs/2609.40328
AB - Cooling an arbitrary mixed state to a pure ground state requires transferring its entropy to an environment. Can a single coherent bath contact accomplish this without repeated bath resets? We develop a new cooling mechanism that transfers the input information into bath degrees of freedom that subsequently decouple, while the system and the remaining bath follow a ground-state path. The bath is discarded only at the end, and the system Hamiltonian remains on and unmodified throughout. We rigorously realize this mechanism for a class of weakly interacting, gapped fermionic systems with local interactions. Starting from any mixed state, our protocol prepares the interacting ground state in total physical time polylogarithmic in the system size and inverse global trace-norm error. It uses two initially empty bath modes per system mode and a single pulse shared across all onsite system--bath couplings. The same pulse prepares each admissible system's own ground state without knowledge of its microscopic parameters. The guarantees follow directly from a non-Markovian system--bath dynamics without an effective Lindbladian description.
ER -