CsYb: MicroKelvin Molecules in a Quantum Array
Ultracold dipolar molecules offer a wide range of potential applications in atomic and molecular physics, ranging from precision measurement of fundamental physics to ultracold quantum chemistry. The goal of this project is to create a quantum degenerate mixture of Yb and Cs confined in a 3D optical lattice and subsequently produce ultracold CsYb molecules. Such molecules possess both a magnetic moment and an electric dipole moment, and therefore offer intriguing possibilities for the quantum simulation of lattice spin models.
We successfully created our first Cs BEC on 30th June 2016. The condensate contained ~ 5 x 104 133Cs atoms. The route to Cs BEC was as follows:
A MOT of 3 x 108 Cs atoms is loaded in 5 s. These atoms are then cooled and compressed via molasses and gradient ramps before being transferred into the Raman lattice. After Raman sideband cooling for 8 ms we obtain 4.5 x107 atoms at T~ 2 µK. These atoms are then transferred into a crossed Resevoir trap created by a 50 W IPG laser at 1070 nm. The reservoir is formed by two 20 W beams crossing at angle of 25˚, with waists 440 µm and 640 µm respectively. We initially load 1.5 x 107 atoms into the reservoir at T= 2.3 µK. We transfer 9 x 105 of these atoms into a dimple trap formed by crossing a 75 µm waist beam with a beam with a 30 µm waist at an angle of 40˚. The bias field is then reduced to 22 G and the sample is evaporatively cooled by reducing the Dimple laser power over 2.5 s. The onset of degeneracy occurs at Tc = 40 nK with N = 7 x 104. We obtain pure condensates of 5 x 104.
"MMQA: Microkelvin Molecules in a Quantum Array" EP/I012044/1. (Dec. 2010 - Dec. 2015). This project forms part of a collaborative project with the Cold Matter group at Imperial College, London.