During my PhD, I studied ways to better control and measure the motion of a single atom. This atom was charged and trapped in an oscillating electric field, then cooled to nearly absolute zero using lasers. When an atom is this cold and well controlled, the rules of quantum physics govern its motion. I could put it in a very non-classical state, where its quantum wavefunction (gold plot on left) was much more complex than the wavefunction of an atom that followed the rules of classical physics (grey feature on left). I could then use these states to very precisely measure how changes in the electric field affected the atom.
McCormick, K. C., Keller, J., Burd, S. C., Wineland, D. J., Wilson, A. C.
and Leibfried, D., Nature 572, 7767 (2019)
McCormick, K. C., Keller, J., Wineland, D. J., Wilson, A. C. and Leibfried, D., Quantum Sci. Technol. 4, 024010
S. L. Todaro, V. B. Verma, K. C. McCormick, D. T. C. Allcock, R. P. Mirin, D. J. Wineland, S. W. Nam, A. C. Wilson, D. Leibfried, and D. H. Slichter, arXiv:2008.00065 (2020)
J. Keller, P.-Y. Hou, K.C. McCormick, D.C. Cole, S.D. Erickson, J.J. Wu, A.C. Wilson, D. Leibfried arXiv:2010.10438 (2020)
For my postdoc, I moved on from studying just one atom to studying thousands to millions of atoms. Instead of just learning about how one isolated quantum object behaves, I want to learn about how objects interact with one another and how they behave collectively. One aspect of interactions between atoms is how they bounce off one another and, sometimes, how they become bound to one another, forming a molecule. I am trying to control this formation of molecules by adjusting the magnetic field near the atoms.
Green, A., Li, H., See Toh, J.H., Tang, X., McCormick, K.C., Li, M., Tiesinga, E., Kotochigova, S., and Gupta, S., Phys. Rev. X 10, 031037 (2020)