News & Research Highlights

NRC Postdoc Ed Marti received an Outstanding Presentation Award for his presentation of the poster "Spin-Orbit Coupled Fermions in an Optical Clock" at the 2016  Boulder Laboratories Postdoctoral Poster Symposium held on July 20. This recognition was shared with NRC Postdoc Shimon Kolkowitz, who originally submitted the abstract as well as prepared the poster and a two-minute–two-slide synopsis of the work. Marti did a great job with both the oral and poster presentations even though he had just one day's notice after family matters kept Dr Kolkowitz from participating in the conference.

Newly minted Ph.D. Ming-Guang Hu and his colleagues in the Jin and Cornell groups recently investigated immersing an impurity in a quantum bath consisting of a Bose-Einstein condensate, or BEC. The researchers expected the strong impurity-boson interactions to “dress” the impurity, i.e., cause it to get bigger and heavier. In the experiment, dressing the impurity resulted in it becoming a quasi particle called a Bose polaron.

Jennifer Ellis won an Optical Society of America (OSA) award in recognition of her excellent oral contribution at the International Conference on Ultrafast Phenomena, held July 17–22 in Santa Fe, New Mexico. Ellis, who is a graduate student with the Kapteyn/Murnane group, spoke about her work on Femtosecond Dynamics of Solvated Electrons in Nanodroplets Probed with Extreme Ultraviolet Beams. She told how her group used EUV light to conduct time-resolved photoemission measurements of isolated nanodroplets in vacuum. With this technique, her group was able to observe what happens when nanodroplets absorb EUV photons. Ellis and her colleagues were able to watch the creation and relaxation of electrons surrounded by solvent molecules––inside the nanodroplets! Congratulations Jennifer!

Bob Peterson and his colleagues in the Lehnert-Regal lab recently set out to try something that had never been done before: use laser cooling to systematically reduce the temperature of a tiny drum made of silicon nitride as low as allowed by the laws of quantum mechanics. Although laser cooling has become commonplace for atoms, researchers have only recently used lasers to cool tiny silicon nitride drums, stretched over a silicon frame, to their quantum ground state. Peterson and his team decided to see just how cold their drum could get via laser cooling.

Adam Kaufman has been awarded the 2016 DAMOP Thesis Prize for his outstanding thesis research on assembling neutral atoms in optical tweezers, work conducted in the Regal group at JILA. As part of this  work, Kaufman and his coworkers developed an experiment that allowed the team to use laser cooling to assemble arrays of ground-state neutral atoms in optical tweezers. 

The Kapteyn/Murnane group has measured how long it takes an electron born into an excited state inside a piece of nickel to escape from its birthplace. The electron’s escape is related to the structure of the metal. The escape is the fastest material process that has been measured before in the laboratory––on a time scale of a few hundred attoseconds, or 10^-18 s. This groundbreaking experiment was reported online in Scienceon June 2, 2016. Also in Science on July 1, 2016, Uwe Bovensiepen and Manuel Ligges offered important insights into the unusual significance of this work. 

The Ye group just solved a major problem for using molecular fingerprinting techniques to identify large, complex molecules: The researchers used an infrared (IR) frequency comb laser to identify four different large or complicated molecules. The IR laser-light absorption technique worked well for the first time with these larger molecules because the group combined it with buffer gas cooling, which precooled their samples to just a few degrees above absolute zero. 

Move over, single-atom laser cooling! The Holland theory group has just come up with a stunning idea for a new kind of laser cooling for use with ensembles of atoms that all “talk” to each other. In other words, the theory looks at laser cooling not from the perspective of cooling a single atom, but rather from the perspective of many atoms working together to rapidly cool themselves to a miniscule fraction of a degree above absolute zero.

The old JILA molecule factory (built in 2002) produced the world’s first ultracold polar molecules [potassium-rubidium (KRb)] in 2008. The old factory has been used since then for ultracold chemistry investigations and studies of the quantum behavior of ultracold molecules and the atoms that form them. The Jin-Ye group, which runs the molecule factory, is now wrapping up operations in the old factory with experiments designed to improve operations in the ultramodern factory, which is close to completion.

The Ye and Rey groups have discovered the strange rules of quantum baseball in which strontium (Sr) atoms are the players, and photons of light are the balls. The balls control the players by not only getting the atoms excited, but also working together. The players coordinate throwing and catching the balls. While this is going on, the balls can change the state of the players! Sometimes the balls even escape the quantum baseball game altogether and land on detectors in the laboratory.

Graduate Student Matt Norcia (Thompson group) received a JILA Scientific Achievement Award on February 18. The announcement took place during a special snack time in the Sunrise Room of the JILA Tower.

Cong Chen and his colleagues in the Kapteyn/Murnane group have generated one of the most complex coherent light fields ever produced using attosecond (10-18 s) pulses of circularly polarized extreme ultraviolet (EUV) light. (The circularly polarized EUV light is shown as rotating blue sphere on the left of the picture. The complex coherent light field is illustrated with the teal, lilac, and purple structures along the driving laser beam (wide red line).

The Rey and Ye groups are in the midst of an extended collaboration on using the Ye group’s strontium (Sr) lattice clock for studies of spin-orbit coupling in pancake-like layers of cold Sr atoms. Spin-orbit coupling means an atom’s motion is correlated with its spin. It occurs in everyday materials when negatively charged electrons move in response to electromagnetic fields inside a crystal.

President Obama has selected JILA Fellow Jun Ye of NIST's Quantum Physics Division to receive a 2015 Presidential Rank Award. The award cited Ye's work advancing "the frontier of light-matter interaction and focusing on precision measurement, quantum physics and ultracold matter, optical frequency metrology, and ultrafast science."

Imagine laser-like x-ray beams that can “see” through materials––all the way into the heart of atoms. Or, envision an exquisitely controlled four-dimensional x-ray microscope that can capture electron motions or watch chemical reactions as they happen. Such exquisite imaging may soon be possible with laser-like x-rays produced on a laboratory optical table. These possibilities have opened up because of new research from the Kapteyn/Murnane group.

In the future, quantum microwave networks may handle quantum information transfer via optical fibers or microwave cables. The evolution of a quantum microwave network will rely on innovative microwave circuits currently being developed and characterized by the Lehnert group. Applications for this innovative technology could one day include quantum computing, converters that transform microwave signals to optical light while preserving any encoded quantum information, and advanced quantum electronics devices.

JILA’s cold molecule collaboration (Jin and Ye Groups, with theory support from the Rey Group) recently made a breakthrough in its efforts to use ultracold polar molecules to study the complex physics of large numbers of interacting quantum particles. By closely packing the molecules into a 3D optical lattice (a sort of “crystal of light”), the team was able to create the first “highly degenerate” gas of ultracold molecules.

The Regal and Rey groups have come up with a novel way to generate and propagate quantum entanglement [1], a key feature required for quantum computing. Quantum computing requires that bits of information called qubits be moved from one location to another, be available to interact in prescribed ways, and then be isolated for storage or subsequent interactions. The group showed that single neutral atoms carried in tiny traps called optical tweezers may be a promising technology for the job!

Scientists often use ultracold atoms to study the behavior of atoms and electrons in solids and liquids (a.k.a. condensed matter). Their goal is to uncover microscopic quantum behavior of these condensed matter systems and develop a controlled environment to model materials with new and advanced functionality.

The Perkins Group has demonstrated a 50-to-100 times improvement in the time resolution for studying the details of protein folding and unfolding on a commercial Atomic Force Microscope (AFM). This enhanced real time probing of protein folding is revealing details in these complex processes never seen before. This substantial enhancement in AFM force spectroscopy may one day have powerful clinical applications, including in the development of drugs to treat disease caused by misfolded proteins. Misfolded proteins are implicated in such fatal maladies as Creutzfeldt–Jakob disease and mad cow disease, both of which are caused by prions.