Prof. Francis Robicheaux I've been a
professor of physics at Purdue University since 2013 (previously at
Auburn University 19932013). My research area is Theoretical Atomic
Physics, mainly focusing on time dependent atomic phenomena, highly
excited (Rydberg) atoms, electron scattering, strong fields and
ultracold plasmas. My research group typically consists of undergrads,
grad students and postdocs. I'm a member of the ALPHA collaboration
which was
the first group to trap the antimatter version of the Hydrogen atom and
the first group to quantitatively measure some of its properties.


Rydberg GasThe frozen Rydberg gas is an interesting new example of a correlated system. We have performed several studies of this system with our focus on a full quantum solution of the developing correlation. Some examples of studies we've performed: 1) a spinecho like effect when a Rydberg gas is created by two or three laser pulses, 2) the hopping of an excitation through the gas, 3) calculations of the dipole blockade that occurs when the atoms are excited by a very narrowband laser, and 4) solution of a model problem to understand whether the correlations in the gas are quantum mechanical or classical. Below is a brief description of results in two recent publications. F. Robicheaux, M.M. Goforth, and M.A. Phillips, "Simulation of prompt manybody ionization in a frozen Rydberg gas," Phys. Rev. A 90, 022712 (2014). PDF (254 kB) An experiment from Tom Gallagher's group strongly suggested that a gas of Rydberg atoms would ionize faster than could be explained by pairs of atoms at the appropriate separation. We performed classical calculations to see whether the number of atoms in a simulation was important or mainly the average density. We performed calculations for 1D, 2D, and 3D arrays of atoms. The main question is what happens when the atoms are randomly distributed as in a gas. F. Robicheaux and N.M. Gill, "Effect of random positions for coherent dipole transport," Phys. Rev. A 89, 053429 (2014). PDF (831 kB) In this calculation, we studied how the random positions for a gas of Rydberg atoms would affect the hopping of an exciton due to the dipoledipole interaction. This system should show effects like Anderson localization. Five Recent
Publications
Hui Yu and F. Robicheaux, "Coherent dipole transport in a small grid of Rydberg atoms," Phys. Rev. A 93, 023618 (2016). PDF (387 kB) F. Robicheaux, M.M. Goforth, and M.A. Phillips, "Simulation of prompt manybody ionization in a frozen Rydberg gas," Phys. Rev. A 90, 022712 (2014). PDF (254 kB) F. Robicheaux and N.M. Gill, "Effect of random positions for coherent dipole transport," Phys. Rev. A 89, 053429 (2014). PDF (831 kB) S. Zhang, F. Robicheaux, and M. Saffman, "Magicwavelength optical traps for Rydberg atoms," Phys. Rev. A 84, 043408 (2011). PDF (820 kB) F. Robicheaux, "Transfer of a wavepacket between atoms," J. Phys. B 43, 215004 (2010). PDF (249 kB) B. Sun and F. Robicheaux, " 
robichf[at]purdue.edu Links: 