Entangled Mechanical Oscillators

TL;DR

This paper demonstrates the first deterministic entanglement between separated mechanical oscillators and between an atomic ion's internal states and a distant mechanical oscillator, advancing understanding of macroscopic quantum phenomena.

Contribution

It presents the novel achievement of entangling separated mechanical oscillators and linking an atomic ion's internal state with a mechanical oscillator, previously unobserved in nature.

Findings

Successful deterministic entanglement of separated mechanical oscillators

Entanglement of atomic ion internal states with a mechanical oscillator

Demonstration of macroscopic quantum entanglement in mechanical systems

Abstract

Hallmarks of quantum mechanics include superposition and entanglement. In the context of large complex systems, these features should lead to situations like Schrodinger's cat, which exists in a superposition of alive and dead states entangled with a radioactive nucleus. Such situations are not observed in nature. This may simply be due to our inability to sufficiently isolate the system of interest from the surrounding environment -- a technical limitation. Another possibility is some as-of-yet undiscovered mechanism that prevents the formation of macroscopic entangled states. Such a limitation might depend on the number of elementary constituents in the system or on the types of degrees of freedom that are entangled. One system ubiquitous to nature where entanglement has not been previously demonstrated is distinct mechanical oscillators. Here we demonstrate deterministic entanglement of separated mechanical oscillators, consisting of the vibrational states of two pairs of atomic ions held in different locations. We also demonstrate entanglement of the internal states of an atomic ion with a distant mechanical oscillator.