Experimental realization of quantum zeno dynamics

TL;DR

This paper experimentally demonstrates quantum Zeno dynamics using a rubidium Bose-Einstein condensate, showing how measurements and strong couplings can control quantum evolution within a multi-level system.

Contribution

It provides the first experimental realization of quantum Zeno dynamics in a Bose-Einstein condensate, illustrating control over quantum state evolution via measurement-induced effects.

Findings

Quantum Zeno dynamics can be realized in a five-level Bose-Einstein condensate.

Measurements and strong couplings can dynamically disconnect quantum states.

Atoms are constrained to evolve coherently within a two-level subspace.

Abstract

It is generally impossible to probe a quantum system without disturbing it. However, it is possible to exploit the back-action of quantum measurements and strong couplings to tailor and protect the coherent evolution of a quantum system. This is a profound and counterintuitive phenomenon known as quantum Zeno dynamics (QZD). Here we demonstrate QZD with a rubidium Bose-Einstein condensate in a five-level Hilbert space. We harness measurements and strong couplings to dynamically disconnect different groups of quantum states and constrain the atoms to coherently evolve inside a two-level subregion. In parallel to the foundational importance due to the realization of a dynamical superselection rule and the theory of quantum measurements, this is an important step forward in protecting and controlling quantum dynamics and, broadly speaking, quantum information processing.