News & Research Highlights

Science, Technology, Engineering, and Mathematics (STEM) education just got a big boost from a new iPad App developed by the PhET Interactive Simulations project at the University of Colorado. The 99¢ App is an extension of the award-winning collection of computer simulations of topics in science and mathematics produced by the project.

Far-red fluorescent light emitted from proteins could one day illuminate the inner workings of life. But before that happens, scientists like Fellow Ralph Jimenez must figure out how fluorescent proteins’ light-emitting structures work. As part of this effort, Jimenez wants to answer a simple question: How do we design red fluorescent proteins to emit longer-wavelength, or redder, light?

Using frequency comb spectroscopy, the Ye group has directly observed transient intermediate steps in a chemical reaction that plays a key role in combustion, atmospheric chemistry, and chemistry in the interstellar medium. The group was able to make this first-ever measurement because frequency combs generate a wide range of laser wavelengths in ultrafast pulses. These pulses made it possible for the researchers to “see” every step in the chemical reaction of OH + CO → HOCO → CO2 + H.

The Proceedings of the National Academy of Sciences has just published a profile of Fellow Henry Kapteyn, a recently elected member of the National Academy of Sciences. The profile presents highlights of Kapteyn's life as well as his long and productive career in developing ultrashort-wavelength lasers, including table-top x-ray lasers. Many of Kapteyn's achievements occurred during a long and fruitful collaboration with his wife, Fellow Margaret Murnane. The profile accompanies Kapteyn’s Inaugural Article entitled "A new regime of nanoscale thermal transport: Collective diffusion increases dissipation efficiency."

The Nesbitt group has invented a nifty technique for exploring the physics and chemistry of a gas interacting with molecules on the surface of a liquid. The group originally envisioned the technique because it’s impossible to overestimate the importance of understanding surface chemistry. For instance, ozone depletion in the atmosphere occurs because of chemical reactions of hydrochloric acid on the surface of ice crystals and aerosols in the upper atmosphere. Interstellar chemistry takes place on the surface of tiny grains of dust.

Exciting new theory from the Rey group reveals the profound effects of electron interactions on the flow of electric currents in metals. Controlling currents of strongly interacting electrons is critical to the development of tomorrow’s advanced microelectronics systems, including spintronics devices that will process data faster, use less power than today’s technology, and operate in conditions where quantum effects predominate.

Fellows Jun Ye and Deborah Jin (1968–2016) have been named Highly Cited Researchers for 2016 by Thomson Reuters. Highly Cited Researchers is an annual list that recognizes leading researchers from around the world based on an analysis of their research publications The 2016 list recognizes the most-cited authors of research publications in the period 2004 through 2014. Ye and Jin are two of 110 people in the physics category in this year's list.

Science News has a delightful profile of Senior Research Associate Tenio Popmintchev as part of the magazines annual feature: The SN10: Meet the scientists making the next big discoveries.

Deborah Jin passed away September 15, 2016, after a courageous battle with cancer. She was 47. Jin was an internationally renowned physicist and Fellow with the National Institute of Standards and Technology (NIST); Professor Adjunct in the Department of Physics at the University of Colorado Boulder, and a Fellow of JILA, a joint institute of NIST and the University of Colorado.

Graduate student Maya Fabrikant has won one of three prizes awarded to the best posters presented by young researchers during the MOLEC 2016 conference held in Toledo, Spain September 11–16. Both graduate students and postdoctoral researchers were eligible for the prizes, which included a $200 Visa gift card. The three prizes were presented by the Journal of Physical Chemistry.

Fellows Cindy Regal and Konrad Lehnert have won the 2016 Governor’s Award for High-Impact Research in Foundational Science and Technology, CO-LABS announced today. JILA Chair Dana Anderson submitted the nomination of their joint research on building, studying, and using devices that exploit the strange and powerful properties of quantum mechanics. The nomination was entitled, The JILA Quantum Machine Team: Extending Mastery of Quantum Mechanics from Microscopic Particles to Human-Made Machines.

The American Chemical Society (ACS) has awarded David Nesbitt the 2017 E. Bright Wilson Award in Spectroscopy. The award, sponsored by the ACS Division of Physical Chemistry, recognizes outstanding accomplishments in fundamental or applied spectroscopy in chemistry. It consists of $5,000 and a certificate.

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.