Doubling Efficiency of Hamiltonian Simulation via Generalized Quantum Signal Processing

TL;DR

This paper demonstrates that by leveraging generalized quantum signal processing, the efficiency of Hamiltonian simulation on quantum computers can be doubled, reducing the computational cost significantly.

Contribution

It introduces a method to halve the cost of Hamiltonian simulation by utilizing generalized quantum signal processing techniques.

Findings

Cost of Hamiltonian simulation reduced by a factor of 2

Utilizes control between forward and reverse steps with similar costs

Builds on recent advances in quantum signal processing

Abstract

Quantum signal processing provides an optimal procedure for simulating Hamiltonian evolution on a quantum computer using calls to a block encoding of the Hamiltonian. In many situations it is possible to control between forward and reverse steps with almost identical cost to a simple controlled operation. We show that it is then possible to reduce the cost of Hamiltonian simulation by a factor of 2 using the recent results of generalised quantum signal processing.