Transient effects in quantum refrigerators with finite environments

A Bhattacharyya, A Ghoshal, U Sen - Physical Review A, 2025 - paper.sciencenet.cn
**日, 印度哈里什-钱德拉研究所的 Ujjwal Sen 及其研究团队取得一项新进展. 经过不懈努力,
他们揭示有限环境下量子制冷机中的瞬态效应. 相关研究成果已于 2025 年 1 月 13 …

Enhancing precision of atomic clocks by tuning disorder in accessories

A Bhattacharyya, A Ghoshal, U Sen - Physical Review A, 2024 - APS
We find that a quantum device having an accessory involving precision measurement can
have an enhancement of its metrological precision in estimating an unknown parameter of …

[PDF][PDF] Disorder-induced enhancement of precision in quantum metrology

A Bhattacharyya, A Ghoshal, U Sen - system, 2023 - academia.edu
We find that insertion of glassy disorder, accidental or engineered, can lead to enhancement
of metrological precision in estimating an unknown parameter of a quantum system. We …

Designing refrigerators in higher dimensions using quantum spin models

TK Konar, S Ghosh, AK Pal, A Sen - Physical Review A, 2023 - APS
We design quantum refrigerators based on spin-j quantum XYZ and bilinear-biquadratic
models with individual spins attached to bosonic thermal baths. By considering both local …

Enhanced efficiency in quantum Otto engine via additional magnetic field and effective negative temperature

A Maity, AS De - arxiv preprint arxiv:2304.10420, 2023 - arxiv.org
A four-stroke quantum Otto engine can outperform when conducted between two thermal
reservoirs, one at a positive spin temperature and the other one at an effective negative spin …

Active quantum distillation

M Yang, DL Zhou - Physical Review A, 2024 - APS
Quantum distillation is a modern technology to decrease the von Neumann entropy of a
subsystem by coherent system dynamics. Here we propose an active quantum distillation …

[HTML][HTML] Advancing Quantum Otto Engine Performance via Additional Magnetic Field and Effective Negative Temperature

A Maity, AS De - Physics Letters A, 2025 - Elsevier
We formulate a protocol for a four-stroke quantum Otto engine that is capable of achieving
superior performance when operating between two thermal reservoirs: one at a positive spin …

Refrigeration via purification through repeated measurements

TK Konar, S Ghosh, A Sen - Physical Review A, 2022 - APS
We design a measurement-based quantum refrigerator with an arbitrary number of qubits
situated in a one-dimensional array that interact through variable-range XY interactions. The …

Stark localization near Aubry-Andr\'{e} criticality

A Sahoo, A Saha, D Rakshit - arxiv preprint arxiv:2404.14971, 2024 - arxiv.org
In this work we investigate the Stark localization near the Aubry-Andr\'{e}(AA) critical point.
We study system-dependent parameters, such as localization length, inverse participation …

Measurement-based qudit quantum refrigerator with subspace cooling

D Ghosh, TK Konar, AS De - arxiv preprint arxiv:2409.08375, 2024 - arxiv.org
We develop a method to transform a collection of higher-dimensional spin systems from the
thermal state with a very high temperature of a local spin-s Hamiltonian to a low-lying energy …