Entanglement in massive coupled oscillators
(pp0278-0299)
Nathan L.
Harshman and William F. Flynn
doi:
https://doi.org/10.26421/QIC11.3-4-7
Abstracts:
This article investigates entanglement of the motional states of massive
coupled oscillators. The specific realization of an idealized diatomic
molecule in one-dimension is considered, but the techniques developed
apply to any massive particles with two degrees of freedom and a
quadratic Hamiltonian. We present two methods, one analytic and one
approximate, to calculate the interatomic entanglement for Gaussian and
nonGaussian pure states as measured by the purity of the reduced density
matrix. The cases of free and trapped molecules and hetero- and
homonuclear molecules are treated. In general, when the trap frequency
and the molecular frequency are very different, and when the atomic
masses are equal, the atoms are highly-entangled for molecular coherent
states and number states. Surprisingly, while the interatomic
entanglement can be quite large even for molecular coherent states, the
covariance of atomic position and momentum observables can be entirely
explained by a classical model with appropriately chosen statistical
uncertainty.
Key words:
continuous-variable entanglement, coupled oscillators,
closed-system entanglement dynamics |