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arXiv · 1710.03145

Controllability in tunable chains of coupled harmonic oscillators

L. F. Buchmann·K. Mølmer·D. Petrosyan
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Abstract

We prove that temporal control of the strengths of springs connecting $N$ harmonic oscillators in a chain provides complete access to all Gaussian states of $N-1$ collective modes. The proof relies on the construction of a suitable basis of cradle modes for the system. An iterative algorithm to reach any desired Gaussian state requires at most $3N(N-1)/2$ operations. We illustrate this capability by engineering squeezed pseudo-phonon states - highly non-local, strongly correlated states that may result from various nonlinear processes. Tunable chains of coupled harmonic oscillators can be implemented by a number of current state-of-the-art experimental platforms, including cold atoms in lattice potentials, arrays of mechanical micro-oscillators, and coupled optical waveguides.

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L. F. Buchmann, K. Mølmer, D. Petrosyan. 2017-10-09. Controllability in tunable chains of coupled harmonic oscillators. https://doi.org/10.1103/physreva.97.042111

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