Saved in:
Bibliographic Details
Main Authors: Liu, Jin-Peng, Lin, Lin
Format: Preprint
Published: 2023
Subjects:
Online Access:https://arxiv.org/abs/2307.14441
Tags: Add Tag
No Tags, Be the first to tag this record!
Table of Contents:
  • The quantum dense output problem is the process of evaluating time-accumulated observables from time-dependent quantum dynamics using quantum computers. This problem arises frequently in applications such as quantum control and spectroscopic computation. We present a range of algorithms designed to operate on both early and fully fault-tolerant quantum platforms. These methodologies draw upon techniques like amplitude estimation, Hamiltonian simulation, quantum linear Ordinary Differential Equation (ODE) solvers, and quantum Carleman linearization. We provide a comprehensive complexity analysis with respect to the evolution time $T$ and error tolerance $ε$. Our results demonstrate that the linearization approach can nearly achieve optimal complexity $\mathcal{O}(T/ε)$ for a certain type of low-rank dense outputs. Moreover, we provide a linearization of the dense output problem that yields an exact and finite-dimensional closure which encompasses the original states. This formulation is related to the Koopman Invariant Subspace theory and may be of independent interest in nonlinear control and scientific machine learning.