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arXiv · 2404.16783

Dual-isometric Projected Entangled Pair States

Xie-Hang Yu·J. Ignacio Cirac·Pavel Kos·Georgios Styliaris
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Abstract

Efficient characterization of higher dimensional many-body physical states presents significant challenges. In this paper, we propose a new class of Project Entangled Pair State (PEPS) that incorporates two isometric conditions. This new class facilitates the efficient calculation of general local observables and certain two-point correlation functions, which have been previously shown to be intractable for general PEPS, or PEPS with only a single isometric constraint. Despite incorporating two isometric conditions, our class preserves the rich physical structure while enhancing the analytical capabilities. It features a large set of tunable parameters, with only a subleading correction compared to that of general PEPS. Furthermore, we analytically demonstrate that this class can encode universal quantum computations and can represent a transition from topological to trivial order.

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Xie-Hang Yu, J. Ignacio Cirac, Pavel Kos, Georgios Styliaris. 2024-04-25. Dual-isometric Projected Entangled Pair States. https://doi.org/10.1103/physrevlett.133.190401

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