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arXiv · 1510.03859

Hybrid quantum-classical approach to correlated materials

Bela Bauer·Dave Wecker·Andrew J. Millis·Matthew B. Hastings·M. Troyer
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Abstract

Recent improvements in control of quantum systems make it seem feasible to finally build a quantum computer within a decade. While it has been shown that such a quantum computer can in principle solve certain small electronic structure problems and idealized model Hamiltonians, the highly relevant problem of directly solving a complex correlated material appears to require a prohibitive amount of resources. Here, we show that by using a hybrid quantum-classical algorithm that incorporates the power of a small quantum computer into a framework of classical embedding algorithms, the electronic structure of complex correlated materials can be efficiently tackled using a quantum computer. In our approach, the quantum computer solves a small effective quantum impurity problem that is self-consistently determined via a feedback loop between the quantum and classical computation. Use of a quantum computer enables much larger and more accurate simulations than with any known classical algorithm, and will allow many open questions in quantum materials to be resolved once a small quantum computer with around one hundred logical qubits becomes available.

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Bela Bauer, Dave Wecker, Andrew J. Millis, Matthew B. Hastings, M. Troyer. 2016-08-29. Hybrid quantum-classical approach to correlated materials. https://doi.org/10.1103/physrevx.6.031045

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