In 1999 Jin and her then PhD student Brian DeMarco were the first researchers to cool a gas of fermionic atoms so low that the effects of quantum degeneracy could be observed. This phenomenon underpins the properties of electrons in solid materials, and the ability to create and control ultracold "Fermi gases" has since provided important insights into superconductivity and other electronic effects in materials. Working with Cindy Regal and Markus Greiner at JILA, Jin later created the first fermionic condensate in 2003, by cooling a gas of potassium atoms to nanokelvin temperatures.
I've always said that she deserves a Nobel Prize in physics for this work. It is also about time that a woman wins this after several deserving ones had been overlooked.