Research on ultra-cold atoms lies at the intersection of atomic physics, many-body physics, quantum optics and quantum information. Quantum physics dominates the behavior of atomic gases cooled to near absolute zero temperature, and cold trapped atoms provide an ideal experimental system for studying quantum many-body physics. Our research focuses on ultra-cold gases of Rubidium atoms and Ytterbium/Rubidium mixtures, with the goals of studying novel condensed matter systems and engineering quantum control over many-body systems, including dissipative baths.
Sub-wavelength structured optical potentials for cold atoms
We recently demonstrated conservative optical lattices with subwavelength spatial structure. (PRL 120 083601 (2018)) The potential is based on the nonlinear optical response of three-level atoms in laser-dressed dark states. Such non-linear response is not constrained by the diffraction limit of the light generating the potential. The lattice consists of a one-dimensional array of ultranarrow barriers with widths less than 10 nm, well below the wavelength of the lattice light, physically realizing a Kronig-Penney potential.
Ancient timekeeping with a modern twist
Trey Porto, a NIST physicist and Fellow of the Joint Quantum Institute, spends his days using atoms and lasers to study quantum physics. But even outside of the lab, he views the world as one great physics problem to tackle. So one morning when he spotted some sunlight dancing across his wall, he couldn’t help but dive in and calculate its movements. He then took his project a step further and began constructing a sundial. Emily sat down with Porto to hear about his clock-making hobby and how today’s time-keeping differs from its ancient counterparts.
This episode of Relatively Certain was produced by Emily Edwards and Chris Cesare. It features music by Dave Depper and Poddington Bear. Relatively Certain is a production of the Joint Quantum Institute, a research partnership between the University of Maryland and the National Institute of Standards and Technology, and you can find it on iTunes, Google Play or Soundcloud.
"Spontaneous avalanche dephasing in large Rydberg ensembles" published
Our follow-up paper to the anamalous broadening work explores the dynamics of the black-body-induced runaway broadening process. Such broadening has serious implications for many proposals to coherently use Rydberg interactions, particularly Rydberg dressing proposals. The dephasing arises as a runaway process where the production of the first contaminant atoms facilitates the creation of more contaminant atoms. Using a pump-probe technique, we create an excess “pump” Rydberg population and probe its effect with a different “probe” Rydberg transition.
Mary is moving on to Stony Brook!
After helping build an experiment from scracth starting with an empty room, we say farewell to Mary! We wish her the best in her new adventures. Here is an early picture of the lab for old times sake.
AJ joins the group
AJ Hachtel joins the interacting photons team, working on Raman cooling of Rb.
Tsz-Chun joins the group
Tsz-Chun Tsui, a first year graduate student, joins the group and promptly passes the qualifier!
Non-linear looped band structure paper published
We published an experimental study of the stability of excited, interacting states of bosons in a double-well optical lattice in
regimes where the nonlinear interactions are expected to induce “swallowtail” looped band structure.
Pierre joins the group
Pierre Bataille joins the group as a visiting masters student from ENS de Cachon.
Daniel returns to Darmstadt!
We say goodbye (for now) to Daniel over a few pints of beer and German food. Daniel is returning to Gerhard Birkl's group to finish his Ph. D.
Brandon joins the group
Brandon Grinkemeyer, a first year undergraduate who worked with us as a high school student, has joined the group.