Experiment

York's research groups offer opportunities in table top atomic physics in the areas of precision measurements, helium and positron spectroscopy, atom interferometry using laser cooled atoms, and Bose Einstein Condensation of atomic gases. York researchers are also key participants in the international ATRAP collaboration dedicated to studies of antihydrogen at CERN.

Eric Hessels

Professor Eric Hessels is a Canada Research Chair and part of a collaboration whose goal is to hold antihydrogen atoms (antimatter versions of the element hydrogen) in a magnetic trap and use them to conduct precise spectroscopic tests of the symmetries and physics of antimatter.  He is also working on using precision measurements of atomic helium to make a a 3-part-per-billion determination of the fine structure constant.
     

A. Kumarakrishnan

Professor A. Kumarakrishnan studies coherent transient phenomena in samples of laser cooled atoms. His work involves making precision measurements of a wide variety of physical parameters utilizing the wave nature of matter via atom interferometry.

Cody Storry

Professor Cody Storry is conducting antimatter research to produce and trap large numbers of antihydrogen atoms. Comparing the atomic structure of antihydrogen and hydrogen provides a direct comparison between matter and antimatter atoms and a strong test of fundamental symmetries in nature. He is also comparing measurements of positronium, an electron bound to an antielectron, to test the predictions of quantum electrodynamics theory.

William van Wijngaarden

Professor William van Wijngaarden has research interests in laser isotope separation, laser cooling, atom trapping, environmental pollutant monitoring, and electromagnetically induced transparency for use in optical switching. His group developed a novel way to use acousto/electro-optic modulators to precisely measure frequency shifts to study hyperfine splittings and Stark shifts. His group was also the first in Canada to create a Bose-Einstein condensate in the lab. 

Theory

The Atomic, Molecular and Opical (AMO) theory group has a strong focus on collision physics ranging from light-particle (electron or positron) scattering from atoms and simple molecules to ion-atom and ion-molecule scattering. Work is also being done on interactions of atoms and molecules with high-intensity lasers. The many-electron problem is dealt with in the framework of time-dependent density functional theory. Other areas of interest include relativistic quantum mechanics, in particular spontaneous electron-positron pair creation by strong fields.

Marko Horbatsch

Professor Marko Horbatsch studies interactions of atoms and simple molecules in collisions with ions or in exposure to strong laser fields by theoretical and computational methods. Particular interests are in the areas of multiple ionization and capture of electrons in collisions of highly charged ions. The emphasis is on developing new computational methods and testing time-dependent density functional theory.

Other interests are in quantum optics, in particular in the line shape problem for high-precision spectroscopy, and in the problem of electron-positron pair creation in ultra-strong fields.

Tom Kirchner

Professor Tom Kirchner's research is concerned with the question of how atomic and molecular few-body systems respond to perturbations exerted on them by impinging particles and external fields. He is working on a method to describe ionization and fragmentation of multi-center molecules. Initial applications of the method are concerned with ion-induced fragmentation of water, which is a relevant process in the radiation damage of biological tissue.   

Allan D. Stauffer

Professor Emeritus Allan Stauffer's does theoretical research in the scattering of electrons and positrons from atoms and simple molecules. He is particularly interested in scattering from heavy atoms and uses the relativistic Dirac equations as the basis for computation of scattering parameters. Much of his work is of use in plasma physics, particularly in the modeling of low pressure plasmas. He maintains close contact with various experimental groups and often publishes joint papers with these groups where theory and experiment can be directly compared.