Analytic continuation average spectrum method for quantum liquids

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.

7 pages, 2 figures

References in corpus (3)

• Using the average spectrum method to extract dynamics from quantum Monte Carlo simulations
• Identifying the maximum entropy method as a special limit of stochastic analytic continuation
• Spin, charge and single-particle spectral functions of the one-dimensional quarter filled Holstein model

Cited by in corpus (14)

• Ab-initio low-energy dynamics of superfluid and solid 4He
• Constrained sampling method for analytic continuation
• Progress on stochastic analytic continuation of quantum Monte Carlo data
• One-dimensional liquid ${}^4$He: dynamical properties beyond Luttinger liquid theory
• Statistical and computational intelligence approach to analytic continuation in Quantum Monte Carlo
• Dynamic structure factor of superfluid He-4 from Quantum Monte Carlo: Maximum Entropy revisited
• Imaginary Time Correlations and the phaseless Auxiliary Field Quantum Monte Carlo
• Spectral Functions from Auxiliary-Field Quantum Monte Carlo without Analytic Continuation: The Extended Koopmans' Theorem Approach
• Stochastic pole expansion method
• Magnon, doublon and quarton excitations in 2D S=1/2 trimerized Heisenberg models
• Single-Particle Dispersion and Density of States of the Half-Filled 2D Hubbard Model
• Cross Validation in Stochastic Analytic Continuation
• Analytical Continuation Approaches to Electronic Transport: The Resonant Level Model
• Hole-induced anomaly in the thermodynamic behavior of a one-dimensional Bose gas