Quantop seminar by Alexander K. Tagantsev

Zoom-link: https://ucph-ku.zoom.us/j/61373330733

What can be made of the “membrane-in-the-middle” cavity?

Abstract 
The so-called “membrane-in-the-middle” cavity is a widely used opto-mechanical system, which typically consists of a one-sided cavity and a mechanical membrane set close to its middle. A modification of that system, where the membrane is set close to the input mirror, was recently [V. Dumont, … .J. C. Sankey, Opt. express 27, 25731 (2019)] addressed. The presented theoretical analysis revealed that, in the case of the highly reflecting membrane, such a system may provide an enhanced opto-mechanical performance.

The present talk dwells upon two other modifications of the classical membrane-in-the-middle cavity: A) the situation where the membrane is set close to the backstop mirror of a one-sided cavity and B) the case where the membrane is set outside but close to the “non-feeding” mirror of a two-sided cavity. The case of the highly reflecting membrane, T << 1 (T is the power transmission of the membrane) is considered. The opto-mechanical performance of such configurations is asserted using the coupling constant and opto-mechanical cooperativity as figures of merit.

It is shown that, if the membrane is properly positioned, the A configuration provides a gain of cooperativity of least of a factor of 2/T vs. other positions of the membrane. The B configuration, with the properly positioned membrane, yields a regime dominated by the dissipative opto-mechanical interaction with the coupling constant and opto-mechanical cooperativity largely exceeding those of other known systems dominated by such an interaction.

F. Elste, S. M. Girvin, and A. A. Clerk, Phys. Rev. Lett. 102, 207209 (2009).
A. Sawadsky, et al Phys. Rev. Lett. 114, 043601 (2015).
A. K. Tagantsev and S. A. Fedorov, Phys. Rev. Lett. 123, 043602 (2019).
A. K. Tagantsev, I. V. Sokolov, and E. S. Polzik, Phys. Rev. A 97, 063820 (2018).
A. K. Tagantsev, and E. S. Polzik, Phys. Rev. A 97 (2021) (in print); arXiv:2102.11842