Pathfinding Quantum Simulations of Neutrinoless Double-Beta Decay

TL;DR

This paper demonstrates quantum simulations of neutrinoless double-beta decay using IonQ's quantum computers, showing real-time lepton-number violation detection and highlighting the potential for future high-resolution nuclear process studies.

Contribution

It introduces a co-designed quantum simulation approach for neutrinoless double-beta decay, utilizing native hardware features and advanced error mitigation on trapped-ion quantum computers.

Findings

Lepton-number violation observed in real time.

High-precision measurement of decay observables achieved.

Effective co-design of algorithms and hardware utilization.

Abstract

We present results from co-designed quantum simulations of the neutrinoless double-beta decay of a simple nucleus in 1+1D quantum chromodynamics using IonQ's Forte-generation trapped-ion quantum computers. Electrons, neutrinos, and up and down quarks are distributed across two lattice sites and mapped to 32 qubits, with an additional 4 qubits used for flag-based error mitigation. A four-fermion interaction is used to implement weak interactions, and lepton-number violation is induced by a neutrino Majorana mass. Quantum circuits that prepare the initial nucleus and time evolve with the Hamiltonian containing the strong and weak interactions are executed on IonQ Forte Enterprise. Enabled by tuned model parameters, lepton-number violation is observed in real time, providing a clear signal of neutrinoless double-beta decay. This was made possible by co-designing the simulation to maximally utilize the all-to-all connectivity and native gate-set available on IonQ's quantum computers. Quantum circuit compilation techniques and co-designed error-mitigation methods, informed from executing benchmarking circuits with up to 2,356 two-qubit gates, enabled observables to be extracted with high precision. We discuss the potential of future quantum simulations to provide yocto-second resolution of the reaction pathways in these, and other, nuclear processes.