# Electro-mechanical Casimir effect

Mikel Sanz1, Witlef Wieczorek2, Simon Gröblacher3, and Enrique Solano1,4,5

1Department of Physical Chemistry, University of the Basque Country UPV/EHU, Apartado 644, E-48080 Bilbao, Spain
2Department of Microtechnology and Nanoscience, Chalmers University of Technology, Kemivägen 9, SE-41296 Göteborg, Sweden
3Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, The Netherlands
4IKERBASQUE, Basque Foundation for Science, Maria Diaz de Haro 3, E-48013 Bilbao, Spain
5Department of Physics, Shanghai University, 200444 Shanghai, China

### Abstract

The dynamical Casimir effect is an intriguing phenomenon in which photons are generated from vacuum due to a non-adiabatic change in some boundary conditions. In particular, it connects the motion of an accelerated mechanical mirror to the generation of photons. While pioneering experiments demonstrating this effect exist, a conclusive measurement involving a mechanical generation is still missing. We show that a hybrid system consisting of a piezoelectric mechanical resonator coupled to a superconducting cavity may allow to electro-mechanically generate measurable photons from vacuum, intrinsically associated to the dynamical Casimir effect. Such an experiment may be achieved with current technology, based on film bulk acoustic resonators directly coupled to a superconducting cavity. Our results predict a measurable photon generation rate, which can be further increased through additional improvements such as using superconducting metamaterials.

Quantum mechanics predicts that virtual particles can emerge from vacuum. This phenomenon, known as quantum fluctuations, is a cornerstone to explaining key effects in nature. The dynamical Casimir effect is an intriguing phenomenon which connects the motion of an accelerated mechanical mirror to the generation of photons. While pioneering experiments about this effect exist, a conclusive measurement involving a mechanical movement of the mirror is still missing. In this Article, we show that a hybrid system consisting of a mechanical resonator coupled to a superconducting cavity may allow to electro-mechanically generate measurable photons from vacuum. Additionally, we also identify the technological challenges which should be faced to improve the process.

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### Cited by

[1] Nicolás F. Del Grosso, Fernando C. Lombardo, and Paula I. Villar, "Photon generation via the dynamical Casimir effect in an optomechanical cavity as a closed quantum system", Physical Review A 100 6, 062516 (2019).

[2] Adrian Parra-Rodriguez, Pavel Lougovski, Lucas Lamata, Enrique Solano, and Mikel Sanz, "Digital-analog quantum computation", Physical Review A 101 2, 022305 (2020).

[3] E. Jansen, J. D. P. Machado, and Ya. M. Blanter, "Realization of a degenerate parametric oscillator in electromechanical systems", Physical Review B 99 4, 045401 (2019).

[4] Miles P. Blencowe and Hui Wang, "Analogue gravity on a superconducting chip", Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378 2177, 20190224 (2020).

[5] Ana Martin, Lucas Lamata, Enrique Solano, and Mikel Sanz, "Digital-analog quantum algorithm for the quantum Fourier transform", Physical Review Research 2 1, 013012 (2020).

[6] Jeferson Danilo L. Silva, Alessandra N. Braga, Andreson L. C. Rego, and Danilo T. Alves, "Motion induced by asymmetric excitation of the quantum vacuum", Physical Review D 102 12, 125019 (2020).

[7] Danilo T. Alves, Edney R. Granhen, João Paulo da S. Alves, and Williams A. Lima, "Relativistic bands in the discrete spectrum of created particles in an oscillating cavity", Physical Review D 102 12, 125012 (2020).

[8] Lilia M. Woods, Matthias Krüger, and Victor V. Dodonov, "Perspective on Some Recent and Future Developments in Casimir Interactions", Applied Sciences 11 1, 293 (2020).

[9] Hui Wang and Miles Blencowe, "Coherently amplifying photon production from vacuum with a dense cloud of accelerating photodetectors", Communications Physics 4 1, 128 (2021).

[10] Wei Qin, Vincenzo Macrì, Adam Miranowicz, Salvatore Savasta, and Franco Nori, "Emission of photon pairs by mechanical stimulation of the squeezed vacuum", Physical Review A 100 6, 062501 (2019).

[11] Hui Wang, M. P. Blencowe, C. M. Wilson, and A. J. Rimberg, "Mechanically generating entangled photons from the vacuum: A microwave circuit-acoustic resonator analog of the oscillatory Unruh effect", Physical Review A 99 5, 053833 (2019).

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