Phase estimation with compressed controlled time evolution
Phys. Rev. A 113, 042420 – Published 8 April, 2026
DOI: https://doi.org/10.1103/j26w-w48j
Abstract
Many optimally scaling quantum simulation algorithms employ controlled time evolution of the Hamiltonian, which is typically the major bottleneck for their efficient implementation. This work establishes a compression protocol for encoding the controlled time evolution operator of translationally invariant local Hamiltonians into a quantum circuit. It achieves a near-optimal in time scaling for circuit depth , while reducing the control overhead from a multiplicative to an additive factor. We report that this compression protocol enables the implementation of iterative quantum phase estimation with as few as 414 controlled-not gates for a frustrated quantum spin system on a triangular lattice and delivers ground-state energy errors below 1% (with % variation, calculated with a hardware noise-aware pipeline) on a triangular lattice using the noisy emulator of the Quantinuum H2 trapped ion device.