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arXiv · 2407.21095

Quantum Simulation via Stochastic Combination of Unitaries

Joseph Peetz·Scott E. Smart·Prineha Narang
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Abstract

Quantum simulation algorithms often require numerous ancilla qubits and deep circuits, prohibitive for near-term hardware. We introduce a framework for simulating quantum channels using ensembles of low-depth circuits in place of many-qubit dilations. This naturally enables simulations of open systems, which we demonstrate by preparing damped many-qubit GHZ states on ibm_hanoi. The technique further inspires two Hamiltonian simulation algorithms with gate counts that are asymptotically independent of the spectral precision target, reducing resource requirements by several orders of magnitude for a benchmark system.

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Joseph Peetz, Scott E. Smart, Prineha Narang. 2024-07-30. Quantum Simulation via Stochastic Combination of Unitaries. https://doi.org/10.1038/s41534-025-01168-w

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