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Algorithm for Linear Response Functions at Finite Temperatures: Application to ESR spectrum of s=1/2 Antiferromagnet Cu benzoate

Toshiaki Iitaka·Toshikazu Ebisuzaki
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Abstract

We introduce an efficient and numerically stable method for calculating linear response functions $χ(\vec{q},ω)$ of quantum systems at finite temperatures. The method is a combination of numerical solution of the time-dependent Schroedinger equation, random vector representation of trace, and Chebyshev polynomial expansion of Boltzmann operator. This method should be very useful for a wide range of strongly correlated quantum systems at finite temperatures. We present an application to the ESR spectrum of s=1/2 antiferromagnet Cu benzoate.

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Toshiaki Iitaka, Toshikazu Ebisuzaki. 2002-12-19. Algorithm for Linear Response Functions at Finite Temperatures: Application to ESR spectrum of s=1/2 Antiferromagnet Cu benzoate. https://doi.org/10.1103/physrevlett.90.047203

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