Title: Recent developments on Ultralong-Range Rydberg Molecules

Speaker:PETER SCHMELCHER

Time: 2025-10-17 15:00

Venue: Room E100, Physics Building

Abstract: A review on the most recent activities in Rydberg molecular physics at the center for optical quantum technologies will be provided. I start out with addressing the exotic properties of ultralong-range Rydberg molecules (ULRM). Trilobite and butterfly states can easily be controlled by weak external electric or magnetic fields. I demonstrate that synthetic dimensions based on quantum numbers can be used to design conical intersections and consequently non-adiabatic interaction effects in the spectra of ULRMs. Ultrafast decay processes are a consequence of these intersections. Quenches of external fields then lead to a rich rovibrational quantum dynamics of ULRM and it is shown that the ULRM is a self-diffracting molecule. Very recently high precision spectroscopy of trilobite molecules has been performed and we present the theory experimental collaboration results. Last, but not least, we show the non-adiabatic stabilization of those molecules in a regime where an adiabatic approach would predict a fast decay into highly energetic products.

Bio: Peter Schmelcher has performed his PhD at the Institute for Physical Chemistry of the University in Heidelberg on the foundations of molecules in strong magnetic fields. He received the Sophie Berntsen Award for his PhD. In the nineties his research focus has been atoms in strong magnetic fields with applications to astrophysics and Rydberg systems culminating in the discovery of the magnetized helium atmospheres of white dwarfs. Since the beginning of the 2000s he has a long-standing expertise on nonlinear waves in Bose-Einstein condensates, strongly correlated ultracold atomic mixtures with an emphasis on their nonequilibrium quantum dynamics. He became a fellow of the American Physical Society and had frequent visits to ITAMP at Harvard. Firstly belonging to the faculty at the University of Heidelberg he moved in 2010 to becoming a faculty member at the University of Hamburg at the center for optical quantum technologies. His research has now a strong focus on Rydberg physics applications to quantum simulation and quantum computing. Besides this, he has developed novel fundamental symmetry concepts based on local and latent symmetries with applications to wave physics. He has been a founding member and leader of several successful excellence initiatives.

References：

[1] R. Srikumar, S.T. Rittenhouse and P. Schmelcher, Physical Review A 110, 062808 (2024).

[2] R. Srikumar, F. Hummel and P. Schmelcher, Physical Review A 108, 012809 (2023).

[3] M. Exner, R. Srikumar, R. Bl¨attner, M.T. Eiles, P. Schmelcher and H. Ott, Physical Review Letters 134, 223401 (2025).

[4] M. Exner, R. Srikumar, R. Bl¨attner, M.T. Eiles, P. Schmelcher and H. Ott, acc.f.publ. Physical Review Research (2025).

[5] F. Hummel, M.T. Eiles and P. Schmelcher, Physical Review Letters 127, 023003 (2021).