Quantum simulation articles from across Nature Portfolio

Achieving thermal observables on a programmable quantum computer is essential for quantum simulation of many-body physics. The authors provide an approach to obtain thermal observables and fluctuations by classically averaging over randomized variants of time evolution under an interacting Hamiltonian, each independently run on a programmable quantum processor.

The complex energy surface of a non-Hermitian system is not single-valued, and windings around its so-called exceptional branching points lead to the chiral and non-reciprocal transfer of eigenstates. Here, the authors experimentally demonstrate such topological state transfers in trapped ion systems, which are being established as promising platforms for quantum simulation.

Simulating many-body systems is a promising application of near-term quantum computers; however, preparing ground states of fermions on a quantum computer is challenging, especially if the ground state is topologically non-trivial. The authors propose a protocol to prepare the ground state of arbitrary fermionic Hamiltonians, which is particularly suitable for topological chiral states.

False vacuum decay is a process of fundamental importance in quantum field theory. Here, a 5,564-qubit quantum annealer is used to simulate the dynamics of false vacuum decay and observe the formation of bubbles of true vacuum. This approach could provide insight into the role of phase transitions in the early Universe.

Many important models in theoretical physics — including the standard model of particle physics — are governed by local ‘gauge’ symmetries. Now, a quantum computer has successfully simulated a lattice gauge theory by leveraging this rich symmetry structure.

Realizing a useful quantum advantage on noisy intermediate-scale quantum hardware is challenging. A proposal now suggests a hybrid digital–analogue hardware-efficient approach for reconfigurable qubit platforms to simulate strongly interacting matter.

Macroscopic fluid dynamics is usually thought to emerge from vast numbers of microscopic particles. Now, fluid-like behaviour has been observed in systems of startlingly few atoms.

A method is introduced to compute provable bounds on noise-free quantum expectation values from noisy samples, promising potential applications in quantum optimization and machine learning.