Laser Physics
Nanoscale materials act differently than their macro counterparts. Using ultra-fast extreme ultraviolet lasers, the KM Goup at JILA has been able to probe silicon carbide as thin as 5 nanometers to understand its strength as it shrinks. This research will help engineers designing ever-shrinking electronics and other technologies.
Scientists understand the rules of equilibrium systems well, but non-equilibrium systems are still a mystery. JILA's Thompson Laboratory and Rey Theory Group collaborated to study how new types of phases of matter emerge in a non-equilibrium system made of atoms and light. This reveals brand new insights into organization principles in out-of-equilibrium matter, and could shed light on how complex systems like black holes behave.
All atoms, molecules and materials are held together by a web of interactions between electrons and ions. In materials, tiny vibrations called phonons cause the positions of the ions to oscillate. How those phonons and electrons are coupled—or interact—determines a material’s properties. The Kapetyn-Murnane Group found that by using ultrafast laser pulses to excite the material, they can precisely study the interaction between electrons and the most important phonons in tantalum diselenide (1T-TaSe2)—and also manipulate it.
Computer chips can’t get much smaller, but they can get faster. That means moving electrons around more quickly. To speed up computers and possibly enable other technologies, scientists want to use light to drive electric currents. The Nesbitt Lab studied gold nanostars and found a way to optically control currents at the nanoscale.
By using optical tweezers, the Kaufman and Ye groups are exploring a new kind of optical atomic clock—one that can run measurements for more than half a minute, an unprecedented coherence time. Not only does this finding open new possibilities for precision measurement, it’s a starting point to engineer interactions between many coherent and carefully-controlled atoms.
Margaret Murnane and Henry Kapteyn are the third married couple to win the coveted award from The Franklin Institute.
Using a new silicon cavity, JILA’s Ye Group has built a laser with improved coherence to reduce the noise in two optical atomic clocks and achieve record high stability. Improving atomic clocks’ stability is crucial to evaluating the clock accuracy and using these tools for scientific experiments in physics and other disciplines.
By using ultrafast lasers to measure the temperature of electrons, JILA researchers have discovered a never-before-seen state in an otherwise standard semiconductor. This research is the most recent demonstration of a new technique, called ultrafast electron calorimetry, which uses light to manipulate well-known materials in new ways.
When the Ye group measured the total quantum state of buckyballs, we learned that this large molecule can play by full quantum rules. Specifically, this measurement resolved the rotational states of the buckyball, making it the largest and most complex molecule to be understood at this level.
CO-LABS presented JILA’s ultrafast imaging team, led by Fellows Margaret Murnane and Henry Kapteyn, the 2018 Governor’s Award for High-Impact Research. Murnane and Kapteyn were honored for their work in revolutionizing ultrafast and nanoscale imaging through the research and development of tabletop x-ray sources. These advancements enable real-time imaging of the structure, chemistry, and dynamics of materials at the level of small collections of atoms. The applications range from improving semiconductor devices and magnetic storage to understanding the fundamental physics and chemistry of complex materials. By designing, developing, and eventually enabling the availability of this technology through KM-Labs, Murnane and Kapteyn have enabled many curious researchers to further their discoveries.