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arXiv · 2312.16169

Quantum squeezing in a nonlinear mechanical oscillator

Stefano Marti·Uwe von Lüpke·Om Joshi·Yu Yang·Marius Bild·Andraz Omahen·Yiwen Chu·Matteo Fadel
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Abstract

Mechanical degrees of freedom are natural candidates for continuous-variable quantum information processing and bosonic quantum simulations. These applications, however, require the engineering of squeezing and nonlinearities in the quantum regime. Here we demonstrate ground state squeezing of a gigahertz-frequency mechanical resonator coupled to a superconducting qubit. This is achieved by parametrically driving the qubit, which results in an effective two-phonon drive. In addition, we show that the resonator mode inherits a nonlinearity from the off-resonant coupling with the qubit, which can be tuned by controlling the detuning. We thus realize a mechanical squeezed Kerr oscillator, where we demonstrate the preparation of non-Gaussian quantum states of motion with Wigner function negativities and high quantum Fisher information. This shows that our results also have applications in quantum metrology and sensing.

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Stefano Marti, Uwe von Lüpke, Om Joshi, Yu Yang, Marius Bild, Andraz Omahen, Yiwen Chu, Matteo Fadel. 2023-12-26. Quantum squeezing in a nonlinear mechanical oscillator. https://arxiv.org/abs/2312.16169

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