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arXiv · 1811.03011

Quantum Hypercube States

L. A. Howard·T. J. Weinhold·F. Shahandeh·J. Combes·M. R. Vanner·A. G. White·M. Ringbauer
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Abstract

We introduce quantum hypercube states, a class of continuous-variable quantum states that are generated as orthographic projections of hypercubes onto the quadrature phase-space of a bosonic mode. In addition to their interesting geometry, hypercube states display phase-space features much smaller than Planck's constant, and a large volume of Wigner-negativity. We theoretically show that these features make hypercube states sensitive to displacements at extremely small scales in a way that is surprisingly robust to initial thermal occupation and to small separation of the superposed state-components. In a high-temperature proof-of-principle optomechanics experiment we observe, and match to theory, the signature outer-edge vertex structure of hypercube states.

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L. A. Howard, T. J. Weinhold, F. Shahandeh, J. Combes, M. R. Vanner, A. G. White, M. Ringbauer. 2018-11-06. Quantum Hypercube States. https://doi.org/10.1103/physrevlett.123.020402

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