Seminarium Optyczne

In cold and ultracold mixtures of atoms and molecules, Rydberg interactions with surrounding atoms or molecules may,under certain conditions, lead to the formation of special long-range Rydberg molecules [1,2,3]. These exotic moleculesprovide an excellent toolkit for manipulation and control of interatomic and atom-molecule interactions, withapplications in ultracold chemistry, quantum information processing and many-body quantum physics.In this talk, we will first discuss ultralong-range polyatomic Rydberg molecules formed when a heteronuclear diatomicmolecule is bound to a Rydberg atom [3,4]. The binding mechanism appears due to anisotropic scattering of theRydberg electron from the permanent electric dipole moment of the polar molecule. We propose an experimentallyrealizable scheme to produce these triatomic ultralong-range Rydberg molecules in ultracold KRb traps, which mightuse the excitation of potassium or rubidium [5]. By exploiting the Rydberg electron-molecule anisotropic dipoleinteraction, we induce a near resonant coupling of the non-zero quantum defect Rydberg levels with the KRb moleculein an excited rotational level. This coupling enhances the binding of the triatomic ultralong-range Rydberg moleculeand produces favorable Franck-Condon factors.Another type of ultralong-range Rydberg molecule is formed in collisions between polar molecules in cold andultracold settings [6]. The interaction of Λ-doublet nitric oxide (NO) with long-lived Rydberg NO molecules formsultralong-range Rydberg bimolecules with GHz energies and kilo-Debye permanent electric dipole moments. Thedescription includes both the anisotropic charge-molecular dipole interaction and the electron-NO scattering. Therotational constant for the Rydberg bimolecules is in the MHz range, allowing for microwave spectroscopy of rotationaltransitions in Rydberg bimolecules. The Rydberg molecules described here hold promise for studies of a special class oflong-range bimolecular interactions. [1] C. H. Greene, A. S. Dickinson, and H. R. Sadeghpour, Phys. Rev. Lett. 85, 2458 (2000).[2] S. T. Rittenhouse and H. R. Sadeghpour, Phys. Rev. Lett. 104, 243002 (2010).[3] V. Bendkowsky, B. Butscher, J. Nipper, J. P. Shaffer, R. Löw, and T. Pfau, Nature 458, 1005 (2009).[4] R. González-Férez, H. R. Sadeghpour, and P. Schmelcher, New J. Phys. 17, 013021 (2015).[5] R. González-Férez, S.T. Rittenhouse, P. Schmelcher and H.R. Sadeghpour, J. Phys. B 53, 074002 (2020).[6] R. González-Férez, J. Shertzer and H. R. Sadeghpour Phys. Rev. Lett. 126, 043401 (2021).