MN2S - Yannick SEIS : "Ground state cooling of an ultracoherent electromechanical system"

We are pleased to welcome Yannick SEIS, postdoctoral researcher at Ecole Normale Supérieure de Lyon. Yannick will give a seminar at 14h00 on March 19 in the JJ Gagnepain theater of the TEMIS building.

Abstract : Cavity electromechanics relies on parametric coupling between microwave and mechanical modes to manipulate the mechanical quantum state, and provide a coherent interface between different parts of hybrid quantum systems. High coherence of the mechanical mode is of key importance in such applications, in order to protect the quantum states it hosts from thermal decoherence. After a brief introduction to the field of optomechanics, we present the characterisation at millikelvin temperatures of a microwave electro-mechanical system featuring an ultra-coherent phononic-crystal membrane. The mechanical dissipation rate is measured down to 30 mK reaching a Q-factor of 1.5 billion, at 1.485 MHz mode frequency. Then we perform resolved sideband cooling on the mechanical mode, cooling it to its motional ground state n_min = 0.76 ± 0.16. We thus show the operation of an electromechanical system in the quantum regime, where its coherence time is estimated to be ~100 ms. We also show microwave-induced mechanical broadening up to 630 Hz, reaching manipulation speeds on the order of state-of-the-art superconducting qubits coherence times making our device a candidate for microwave quantum memories.

Reference: https://www.nature.com/articles/s41467-022-29115-9

Though we prefer that you attend the seminar physically, please feel free to attend on line as well!

Sujet : Séminaire Yannick Seis Heure: 19 mars 2024 14:00 Paris

Rejoindre Zoom Réunion : https://cnrs.zoom.us/j/95088198067?pwd=TzdEZCtsSmltTWhvTnNVaFJHb1BlZz09