Entanglement of bosonic modes of nonplanar molecules

TL;DR

This paper investigates entanglement dynamics between bosonic vibrational modes in coupled nonlinear oscillators, specifically in dihalomethanes, revealing conditions for generating maximally entangled states.

Contribution

It introduces a model of coupled vibrational modes with invariant subspaces, analyzing entanglement generation and dynamics in these systems.

Findings

Invariant subspaces exist due to bilinear coupling.

Initial energy distribution affects entanglement evolution.

Maximally entangled states can be generated under certain conditions.

Abstract

Entanglement of bosonic modes of material oscillators is studied in the context of two bilinearly coupled, nonlinear oscillators. These oscillators are realizable in the vibrational-cum-bending motions of C-H bonds in dihalomethanes. The bilinear coupling gives rise to invariant subspaces in the Hilbert space of the two oscillators. The number of separable states in any invariant subspace is one more than the dimension of the space. The dynamics of the oscillators when the initial state belongs to an invariant subspace is studied. In particular, the dynamics of the system when the initial state is such that the total energy is concentrated in one of the modes is studied and compared with the evolution of the system when the initial state is such wherein the modes share the total energy. The dynamics of quantities such as entropy, mean of number of quanta in the two modes and variances in the quadratures of the two modes are studied. Possibility of generating maximally entangled states is indicated.