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SU(N) fermion systems are multi-component, spin-symmetrical collections of atoms—which are unique among degenerate gases. The Ye Group found that SU(N) fermion systems display special properties that allow them to be quickly cooled and prepared for use in quantum-matter based atomic clocks.

Famous thought experiment Schrödinger’s Cat posits that a quantum system can be in two opposing states simultaneously—a specific type of superposition. Creating cat states in a large number of atoms has been difficult for physicists. The Rey Theory Group has developed a new means of preparing these cat states in the state-of-the-art strontium optical atomic clock. Cat states could in turn improve the sensitivity of the clock beyond what is possible with independent atoms.

Cooling and trapping atoms has helped scientists advance their understanding of atomic and quantum physics over several decades. Now it’s time to move on to more complex systems, like molecules. But molecules have proven tricky to cool and trap efficiently. A new study from the Ye Lab has found a way to cool yttrium monoxide robustly and efficiently, which will allow them to study how they interact with each other in the quantum regime.

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.

The Office of Naval Research program rewards early career scientists “who show exceptional promise for doing creative research”—and JILA's Adam Kaufman's work with optical tweezers has earned that recognition.

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.

Strontium is an incredible element at the center of quantum physics tools and studies—most famously optical atomic clocks. While strontium atoms have one very long-lived excited state (which lives more than 100 seconds), they also have nicely accessible excited states. Those excited states are easier to access, but they are short-lived. A new proposal from the Rey Theory Group suggests a way to reach a dark state where the atoms can live in this excited state forever, opening new opportunities for clock technologies.

Analysis and new designs of low mass SiN mechanical defects in 2D acoustic shields for force sensing -- now published in Physical Review Applied.

Understanding how three atoms interact when they are close together is really tricky. For the past decade scientists agreed that there was a universal “sweet spot”, a range called the van der Waals universality. In that range, three atoms were close enough that their interactions could be explained with simpler two-body formulas. But the Cornell Group at JILA is testing the limits of van der Waals universality, which could help form a better predictive model for other atom species.

For the first time, JILA scientists are able to observe dynamical phase transitions in an out-of-equilibrium system. They also found that they could undo the dynamical changes, reversing the experiment to where it started, which has great implications for understanding how the quantum world behaves and acts as a model for superconductors.