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arXiv · 2302.10935

Complex path simulations of geometrically frustrated ladders

Elyasaf Y. Cohen·Andrei Alexandru·Snir Gazit
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Abstract

Quantum systems with geometrical frustration remain an outstanding challenge for numerical simulations due to the infamous numerical sign problem. Here, we overcome this obstruction via complex path integration in a geometrically frustrated ladder of interacting bosons at finite density. This enables studies of the many-body ground state properties, otherwise inaccessible with standard quantum Monte Carlo methods. Specifically, we study a chemical potential tuned quantum phase transition, along which we track the emergence of quasi-long-range order and critical softening of the single particle gap. We chart future methodological improvements and applications in generalized geometrically frustrated lattice models.

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Elyasaf Y. Cohen, Andrei Alexandru, Snir Gazit. 2023-02-21. Complex path simulations of geometrically frustrated ladders. https://doi.org/10.1103/physrevb.109.115122

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