Najbliższe Konwersatorium Fizyczne OK PTF odbędzie się w dniu 1 grudnia 2022r. o godz. 16:15, w sali A-1-06 Wydziału WFAIS, na III Kampusie UJ, ul. Łojasiewicza 11, 30-348 Kraków.
Dr Michał Parniak (Centre for Quantum Optical Technologies, Centre of New Technologies, University of Warsaw) wygłosi referat: „Multimode quantum optics with hybrid systems”.

Streszczenie:
Hybrid quantum systems may be composed of distinct subsystems with characteristics and different properties. This allows such systems to share the advantages of both components. In quantum optics, light may be used to couple different subsystems, for example for the purpose of enhanced quantum metrology or communication.

In my experiments, I have worked with several systems and tried to combine their unique properties. In one combination, we used light to entangle a macroscopic membrane resonator with a spin ensemble. The membrane resonator was first put into the ground state via optical sideband cooling. Subsequently, a joint measurement of two systems was used to prepare an entangled state.

In another work, we used atoms to couple two distinct domains of electromagnetic radiation. Our lab uses Rydberg atoms to convert microwave photons to optical photons in the near-infrared band. The wave mixing process that made this possible occurred in atoms in a vacuum cell at room temperature, where Doppler broadenings were partially compensated for by geometry selection. Most significantly, microwave photons can be efficiently absorbed due to the large dipole moment between the Rydberg states of nD and (n-1)F (n=55). In the experiment, we achieved a conversion with a photon efficiency of about 1%, which proved sufficient to observe the converted blackbody radiation with a superconducting optical photon counter. Thus, our system allowed us to detect microwaves with a noise temperature below 30 K, despite conversion at room temperature. Such an all-optical converter allows for record sensitivity in microwave detection, which could find applications in radar systems or radio astronomy. In addition, this type of interface will be important for creating quantum optical interconnects ("quics") between quantum computers working in the microwave domain.

In my talk, I would like to introduce the new quantum optical methods to tackle hybrid systems and present their advantages for quantum-enhanced protocols.

Przed referatem (15.45) organizatorzy zapraszają na kawę.