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arXiv · 2201.10974

Excitations of Quantum Many-Body Systems via Purified Ensembles: A Unitary-Coupled-Cluster-based Approach

Carlos L. Benavides-Riveros·Lipeng Chen·Christian Schilling·Sebastián Mantilla·Stefano Pittalis
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Abstract

State-average calculations based on mixture of states are increasingly being exploited across chemistry and physics as versatile procedures for addressing excitations of quantum many-body systems. If not too many states should need to be addressed, calculations performed on individual states is also a common option. Here we show how the two approaches can be merged into one method, dealing with a generalized yet single pure state. Implications in electronic structure calculations are discussed and for quantum computations are pointed out.

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Carlos L. Benavides-Riveros, Lipeng Chen, Christian Schilling, Sebastián Mantilla, Stefano Pittalis. 2022-01-26. Excitations of Quantum Many-Body Systems via Purified Ensembles: A Unitary-Coupled-Cluster-based Approach. https://doi.org/10.1103/physrevlett.129.066401

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