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Related papers: Bath Assisted Cooling of Spins

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We consider the relaxation dynamics of two spins coupled to a common bosonic bath. The time evolution is simulated by a generalized master equation derived within a real-time diagrammatic approach. Interference effects due to the coherent…

Mesoscale and Nanoscale Physics · Physics 2020-02-18 Philipp Stegmann , Jürgen König , Björn Sothmann

We investigate the relaxation of two collective spins in double domain system, which are individually coupled to a single bosonic reservoir, by varying the total number of spins in each domain and their initial spin configurations. A…

Quantum Physics · Physics 2018-02-14 Yusuke Hama , William J. Munro , Kae Nemoto

We propose a technique for polarizing and cooling finite many-body classical systems using feedback control. The technique requires the system to have one collective degree of freedom conserved by the internal dynamics. The fluctuations of…

Quantum Physics · Physics 2022-04-04 Tarek A. Elsayed , Boris V. Fine

Heat-Bath Algorithmic cooling (HBAC) techniques provide ways to selectively enhance the polarization of target quantum subsystems. However, the cooling in these techniques are bounded. Here we report the first experimental observation of…

We consider a spin chain of fermionic atoms in an optical lattice, interacting with each other by super-exchange interactions. We theoretically investigate the dissipative evolution of the spin chain when it is coupled by magnetic…

Quantum Gases · Physics 2018-07-23 M. Robert-de-Saint-Vincent , P. Pedri , B. Laburthe-Tolra

We analyze the effect of a bath of spins interacting with a spin system in terms of the equation of motion technique. We show that this formalism can be used with general spin systems and baths, and discuss the concrete case of a Quantum…

Strongly Correlated Electrons · Physics 2019-09-23 Álvaro Gómez-León , Tim Cox , Philip Stamp

A low temperature model system consisting of a central spin coupled to a spin-bath is studied to determine whether interaction among bath spins has an effect on central spin dynamics. In the absence of intra-environmental coupling,…

Quantum Physics · Physics 2007-05-23 L. Tessieri , J. Wilkie

We study the decoherence of two coupled spins that interact with a spin-bath environment. It is shown that the connectivity and the coupling strength between the spins in the environment are of crucial importance for the decoherence of the…

Quantum Physics · Physics 2011-01-14 S. Yuan , M. I. Katsnelson , H. De Raedt

We study theoretically the cooling of an ensemble of nuclear spins coupled to the spin of a localized electron in a quantum dot. We obtain a master equation for the state of the nuclear spins interacting with a sequence of polarized…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 H. Christ , J. I. Cirac , G. Giedke

We consider a spin-$j$ particle coupled to a structured bath of bosonic modes that decay into thermal baths. We obtain an analytic expression for the reduced spin state and use it to investigate non-Markovian spin dynamics. In the heavily…

Quantum Physics · Physics 2022-04-06 Mattias T. Johnsson , Ben Q. Baragiola , Thomas Volz , Gavin K. Brennen

We experimentally demonstrate that the decoherence of a spin by a spin bath can be completely eliminated by fully polarizing the spin bath. We use electron paramagnetic resonance at 240 gigahertz and 8 Tesla to study the spin coherence time…

Quantum Physics · Physics 2009-11-13 Susumu Takahashi , Ronald Hanson , Johan van Tol , Mark S. Sherwin , David D. Awschalom

Engineering spin polarization in dissipative bosonic systems is crucial for advancing quantum technologies, especially for applications in quantum metrology and space-based quantum simulations. This work demonstrates precise magnetic moment…

Quantum Gases · Physics 2025-06-24 Yaoyuan Fan , Shuoyu Shi , Lang Cao , Qiuxin Zhang , Dong Hu , Yu Wang , Xiaoji Zhou

We present here algorithmic cooling (via polarization-heat-bath)- a powerful method for obtaining a large number of highly polarized spins in liquid nuclear-spin systems at finite temperature. Given that spin-half states represent (quantum)…

Quantum Physics · Physics 2009-11-07 P. Oscar Boykin , Tal Mor , Vwani Roychowdhury , Farrokh Vatan , Rutger Vrijen

Algorithmic cooling (AC) is a method to purify quantum systems, such as ensembles of nuclear spins, or cold atoms in an optical lattice. When applied to spins, AC produces ensembles of highly polarized spins, which enhance the signal…

We propose a cooling scheme based on depolarisation of a polarised cloud of trapped atoms. Similar to adiabatic demagnetisation, we suggest to use the coupling between the internal spin reservoir of the cloud and the external kinetic…

Quantum Physics · Physics 2009-11-11 S. Hensler , A. Greiner , J. Stuhler , T. Pfau

We investigate the evolution of a central spin coupled to a spin bath without internal dynamics. We compare the cases where the bath couples to one or two components of the spin. It is found that the central spin dynamics is enhanced in the…

Mesoscale and Nanoscale Physics · Physics 2009-07-22 D. D. Bhaktavatsala Rao , Heiner Kohler , Fernando Sols

The dynamics of a spin-1/2 particle coupled to a nuclear spin bath through an isotropic Heisenberg interaction is studied, as a model for the spin decoherence in quantum dots. The time-dependent polarization of the central spin is…

Quantum Physics · Physics 2007-06-28 D. D. Bhaktavatsala Rao , V. Ravishankar , V. Subrahmanyam

Decoherence of a central spin coupled to an interacting spin bath via inhomogeneous Heisenberg coupling is studied by two different approaches, namely an exact equations of motion (EOMs) method and a Chebyshev expansion technique (CET). By…

Mesoscale and Nanoscale Physics · Physics 2016-01-20 Ning Wu , Nina Fröhling , Xi Xing , Johannes Hackmann , Arun Nanduri , Frithjof B. Anders , Herschel Rabitz

The spin-boson model, often used in NMR and ESR physics, quantum optics and spintronics, is considered in a solvable limit to model a spin one-half particle interacting with a bosonic thermal bath. By applying external pulses to a…

Statistical Mechanics · Physics 2009-11-07 A. E. Allahverdyan , Th. M. Nieuwenhuizen

In the framework of nuclear magnetic resonance, we consider the general problem of the coherent control of a spin coupled to a bath by means of composite or continuous pulses of duration $\tau_\mathrm{p}$. We show explicity that it is…

Quantum Physics · Physics 2010-03-16 S. Pasini , P. Karbach , C. Raas , G. S. Uhrig