Group Seminar via Zoom:  Probing molecular physics with a quantum gas microscope

April 28, 2020

Simon Hollerith, MPQ
group meeting via Videoconference (Zoom)
Tuesday, April 28th, 9:00 ( MEZ)

Dealing with the unique situation of partial lock downs worldwide and home office solutions at our Institute due to the current spreading of the Covid 19 virus, we are now holding our group seminars and journal clubs via video conference.
This procedure enables us to continue our research, enhance discussions and exchange important information.


Rydberg macrodimers - molecules consisting of two bound highly excited Rydberg atoms - provide huge bond lengths even resolvable with optical wavelengths. Here we report on a microscopic study of macrodimers with different molecular symmetries in a gas of ultracold atoms in an optical lattice. The size of about 0.7 micrometers matches the diagonal distance of two atoms in the lattice. The geometry of the two-dimensional lattice initially unity filled with ground state atoms allows to control the relative orientation of the molecular axis to an ambient magnetic field and the polarization of the photoassociation light. Using our spatially resolved detection, we observe the associated molecules by correlated atom loss and find characteristic state-dependent features in the photoassociation mechanism. Furthermore, we present how the molecular excitation rate can be significantly enhanced by the use of two color photoassociation. In a Ramsey sequence, we show that off-resonant coupling to molecular resonances can be used to engineer interaction potentials peaking at the molecular bond length for ground state atoms. Finally, we present the observation of a macrodimer-macrodimer blockade by evaluating our images with respect to g(4) correlators after a two microseconds excitation pulse at maximum coupling rate. Our results highlights the potential of quantum gas microscopy for molecular physics and show how macrodimers could be used to study many body physics.

If you would like to join our group seminars via Zoom, please contact us for more information.

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