Theoriekolloquium Physik: „From analog simulations of small-polaron physics to W-state engineering with a superconducting qubit-resonator system“

09.12.2019, 16:15

09.12.2019 16:15-17:15

Speaker: Dr. Vladimir M. Stojanovic, TU Darmstadt | Location: Hochschulstraße 8 (S2|04), Room 213, Darmstadt

Organizer: Prof. Gernot Alber

In this talk, a system that consists of inductively-coupled superconducting qubits and microwave resonators will first be introduced. It will then be shown how this system can be utilized as an analog simulator of an important phenomenon from solid-state physics. Namely, it can be used to simulate static and dynamic properties of small polarons -- quasiparticles resulting from a strong, short-ranged interaction of an itinerant excitation (electron, hole) with Einstein-like phonons.

In particular, it allows one to glean new insights into the nonequilibrium aspects of small-polaron physics. In the sequel of this talk, it will be demonstrated how the same system -- used in a different regime of its main experimental knob -- can be exploited for quantum-state engineering. To be more specific, unconventional ground-state properties of the system in the relevant parameter regime allow deterministic preparation of multipartite W states. It will be shown that the envisioned state-preparation protocol allows one to obtain W states within times three orders of magnitude shorter than the currently achievable T_2 coherence times of superconducting transmon qubits.