Sep 17, 2019 4:00 pm - Nielsen Hall 270 - Colloquium
Arne Schwettmann - OU
Harnessing entanglement in microwave-dressed sodium spinor Bose-Einstein condensates

Bose-Einstein condensates provide a fascinating window into the quantum world, presenting us with macroscopic quantum objects to probe and investigate. In this talk, I will discuss how we created OU’s first Bose-Einstein condensate by cooling a gas of sodium atoms in an optical trap to nanokelvin temperatures. Compared to a scalar condensate, where only one atomic spin state is present, our condensate has the advantage that all atomic spin states are trapped and overlapping. This allows for coherent spin-changing collisions to take place, creating entanglement between atoms. Recently, we have learned that the spin-changing collisions as well as the initial spin state can be exquisitely controlled via microwave-dressing. I will present our work on extending this microwave control into the new regime of long evolution times, t>>h/c, where c is the collisional energy, and to seeded initial states, where some atoms are prepared in spin states with magnetic quantum numbers m=+1 and m=-1. I will present our results on implementing an atom interferometer and a phase-sensitive amplifier in this system, useful for future quantum technologies in matter-wave quantum optics, such as quantum-enhanced sensors based on spinor Bose-Einstein condensates.