Quantum Computation of Hydrogen Bond Dynamics and Vibrational Spectra

Abstract

Calculating the observable properties of chemical systems is often classically intractable and is widely viewed as a promising application of quantum information processing. Yet one of the most common and important chemical systems in nature - the hydrogen bond - has remained a challenge to study using quantum hardware on account of its anharmonic potential energy landscape. Here, we introduce a framework for solving hydrogen-bond systems and more generic chemical dynamics problems using quantum logic. We experimentally demonstrate a proof-of-principle instance of our method using the QSCOUT ion-trap quantum computer, in which we experimentally drive the ion-trap system to emulate the quantum wavepacket of the shared-proton within a hydrogen bond. Following the experimental creation of the shared-proton wavepacket, we then extract measurement observables such as its time-dependent spatial projection and its characteristic vibrational frequencies to spectroscopic accuracy (3.3 cm${}^{-1}$ wavenumbers, corresponding to > 99.9% fidelity). Our approach introduces a new paradigm for studying the quantum chemical dynamics and vibrational spectra of molecules, and when combined with existing algorithms for electronic structure, opens the possibility to describe the complete behavior of complex molecular systems with unprecedented accuracy.

18 pages, 5 figures plus supplementary material

References in corpus (7)

• Simulated Quantum Computation of Molecular Energies
• Manipulation and Detection of a Trapped Yb+ Ion Hyperfine Qubit
• Quantum Computation of Electronic Transitions using a Variational Quantum Eigensolver
• Dynamics and Infrared Spectroscopy of the Protonated Water Dimer
• An Introduction to Cartan's KAK Decomposition for QC Programmers
• Observation of wave-packet branching through an engineered conical intersection
• Quantum Simulation of Bosons with the Contracted Quantum Eigensolver

Cited by in corpus (7)

• Predicting molecular vibronic spectra using time-domain analog quantum simulation
• Simulating Vibrational Dynamics on Bosonic Quantum Devices
• Interaction graph engineering in trapped-ion quantum simulators with global drives
• Refining resource estimation for the quantum computation of vibrational molecular spectra through Trotter error analysis
• Quantum nuclear dynamics on a distributed set of ion-trap quantum computing systems
• Quantum circuit and mapping algorithms for wavepacket dynamics: case study of anharmonic hydrogen bonds in protonated and hydroxide water clusters
• Quantum algorithm for solving generalized eigenvalue problems with application to the Schrödinger equation