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Related papers: Prospects and Limitations of Algorithmic Cooling

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We investigate electron cooling based on a clean normal-metal/spin-filter/superconductor junction. Due to the suppression of the Andreev reflection by the spin-filter effect, the cooling power of the system is found to be extremely higher…

Mesoscale and Nanoscale Physics · Physics 2015-04-03 Shiro Kawabata , Andrey S. Vasenko , Asier Ozaeta , F. Sebastian Bergeret , Frank W. J. Hekking

Current and near term quantum computers (i.e. NISQ devices) are limited in their computational power in part due to qubit decoherence. Here we seek to take advantage of qubit decoherence as a resource in simulating the behavior of real…

The description of the tunneling of a macroscopic variable in the presence of a bath of localized spins is a subject of great fundamental and practical interest, and is relevant for many solid-state qubit designs. Instead of focusing on the…

Mesoscale and Nanoscale Physics · Physics 2007-12-05 Andrea Morello , L. J. de Jongh

Simulated cooling is a robust method for preparing low-energy states of many-body Hamiltonians on near-term quantum simulators. In such schemes, a subset of the simulator's spins (or qubits) are treated as a ``bath,'' which extracts energy…

Strongly Correlated Electrons · Physics 2025-04-01 Gilad Kishony , Mark S. Rudner , Achim Rosch , Erez Berg

We analyze the performance of a quantum Otto cycle, employing time-dependent harmonic oscillator as the working fluid undergoing sudden expansion and compression strokes during the adiabatic stages, coupled to a squeezed reservoir. First,…

Quantum Physics · Physics 2021-01-04 Varinder Singh , Özgür E. Müstecaplıoğlu

Cooling of particles to mK-temperatures is essential for a variety of experiments with trapped charged particles. However, many species of interest lack suitable electronic transitions for direct laser cooling. We study theoretically the…

The efficiency of a quantum heat engine is maximum when the unitary strokes are adiabatic. On the other hand, this may not be always possible due to small energy gaps in the system, especially at the critical point where the gap vanishes.…

Quantum Physics · Physics 2024-07-08 Revathy B. S , Harsh Sharma , Uma Divakaran

We provide a versatile analytical framework for calculating the dynamics of a spin system in contact with a fermionic bath beyond the Markov approximation. The approach is based on a second order expansion of the Nakajima-Zwanzig master…

Mesoscale and Nanoscale Physics · Physics 2019-10-18 Stephanie Matern , Daniel Loss , Jelena Klinovaja , Bernd Braunecker

The optimal control of open quantum systems is a challenging task but has a key role in improving existing quantum information processing technologies. We introduce a general framework based on Reinforcement Learning to discover optimal…

Quantum Physics · Physics 2022-01-19 Paolo Andrea Erdman , Frank Noé

The performance of endoreversible thermal machines operating at finite power constitutes one of the main challenges of nonequilibrium classical and quantum thermodynamics, engineering and others. We introduce the idea of adjusting the…

Statistical Mechanics · Physics 2021-06-16 Pedro E. Harunari , Fernando S. Filho , Carlos E. Fiore , Alexandre Rosas

We develop a method of non-perturbative optical control over adiabatic remagnetisation of the nuclear spin system and apply it to verify the spin temperature concept in GaAs microcavities. The nuclear spin system is shown to exactly follow…

We describe how sideband cooling techniques may be applied to large spin ensembles in magnetic resonance. Using the Tavis-Cummings model in the presence of a Rabi drive, we solve a Markovian master equation describing the joint spin-cavity…

Quantum Physics · Physics 2014-02-25 Christopher J. Wood , Troy W. Borneman , David G. Cory

Sympathetic laser cooling is a key concept in precision spectroscopy and quantum state control of charged particles. Significant challenges arise in the metrologically relevant case where the effective interaction between the particles is…

A wide variety of nuclear magnetic resonance experiments rely on the prediction and analysis of relaxation processes. Recently, innovative approaches have been introduced where the sample travels through a broad range of magnetic fields in…

We propose an energy relaxation mechanism whereby strongly correlated spin systems decay into their ground states. The relaxation is driven by cavity quantum electrodynamics interaction and the decay of cavity photons. It is shown that by…

Quantum Physics · Physics 2014-07-08 Jaeyoon Cho , Sougato Bose , M. S. Kim

We propose and experimentally demonstrate a new cooling mechanism leading to purification of a spinor Bose-Einstein Condensate (BEC). Our scheme starts with a BEC polarized in the lowest energy spin state. Spin excited states are thermally…

An exact reduced dynamical map along with its operator sum representation is derived for a central spin interacting with a thermal spin environment. The dynamics of the central spin shows high sustainability of quantum traits such as…

Quantum Physics · Physics 2017-11-23 Chiranjib Mukhopadhyay , Samyadeb Bhattacharya , Avijit Misra , Arun Kumar Pati

Strongly interacting fermions underpin some of the most challenging problems in condensed matter physics, such as high-temperature superconductivity. The low-energy states of these systems encode their essential microscopic properties, yet…

Strongly Correlated Electrons · Physics 2026-05-05 Henning Schlömer , Liyuan Chen , Susanne F. Yelin , Hong-Ye Hu

We calculate the quartet potential energy surface for Li+NH and use it to calculate elastic and spin-relaxation cross sections for collisions in magnetically trappable spin-stretched states. The potential is strongly anisotropic but…

Application of a negative field on a positively poled ferroelectric sample can enhance the electrocaloric cooling and appears as a promising method to optimize the electrocaloric cycle. Experimental measurements show that the maximal…

Materials Science · Physics 2016-11-21 Yang-Bin Ma , Nikola Novak , Karsten Albe , Bai-Xiang Xu