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arXiv · 0905.4148

Analytic continuation average spectrum method for quantum liquids

David R. Reichman·Eran Rabani
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Abstract

We revisit the problem of determining the real-frequency density response in quantum fluids via analytical continuation of imaginary-time quantum Monte Carlo data. We demonstrate that the average spectrum method (ASM) is capable of revealing resolved modes in the dynamic structure factor of both ortho-deuterium and liquid para-hydrogen, in agreement with experiments and quantum mode-coupling theories, while the maximum entropy approach yields only a smooth unimodal spectrum. Outstanding issues are discussed. Our work provides the first application of the ASM method in realistic off-lattice systems.

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David R. Reichman, Eran Rabani. 2009-05-26. Analytic continuation average spectrum method for quantum liquids. https://doi.org/10.1063/1.3185728

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