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Journal of Modern Physics

A Study of Entropy Change in a Spin Quantum System

Paul Bracken

Published Jan 1, 2023• 0 citations
Publisher

Abstract

The entropy change in a spin system coupled to a magnetic field is investigated by solving an evolution equation for a quantum spin system. Entropy of the system is discussed and the exchange of entropy between the spins and field can be studied. The full quantum treatment of spins and field shows that the coherent nature of this field is very important for reaching the spin echo.

DOI
10.4236/jmp.2023.147057

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The entropy change in a spin system coupled to a magnetic field is investigated by solving an evolution equation for a quantum spin system. Entropy of the system is discussed and the exchange of entropy between the spins and field can be studied. The full quantum treatment of spins and field shows that the coherent nature of this field is very important for reaching the spin echo.
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