Funds from this grant support an effort by Professor Eric Hessels at York University, Professor Amar Vutha at the University of Toronto, and Assistant Professor Jaideep Singh at Michigan State University to build advanced instrumentation capable of detecting new fundamental particles through precision measurement of the distortions these particles cause to the distribution of electric charge in an electron.К Hessels, Vutha, and SinghХs primary detection strategy is to trap barium fluoride molecules in a matrix of solid argon. Once held, the electrons in these trapped molecules can be measured for distortions in the distribution of their electric charge. This methodology has several significant theoretical benefits over competing methods. First, holding molecules still, as a solid matrix would, allows the molecules to be measured for thousands of times longer than using molecules in motion. Second, molecules can be very densely packed in a solid matrixСthe York University team will aim to trap a few billionСthereby increasing the number of detection measurements that can be made per unit of space. The method faces obstacles as there is uncertainty about whether a precision measurement can be performed on molecules embedded in a solid matrix. Phonon vibrations of the solid or other effects could make precision measurement of the trapped molecules impractical. The York team will implant the barium fluoride molecules into a solid argon matrix while it is being grown, and then perform spectroscopic measurements on the embedded molecules to see if a precision measurement is practical. In situdiagnostics will probe the growth and implantation process and different growth and annealing schedules will be followed to optimize the platform. If successful, the method could improve our detection capabilities by a factor of 200. The project will lead to six papers, talks and posters at relevant conferences, and training for 30 students and postdoctoral researchers over the project's three-year arc.

Funds from this grant support efforts by researchers led by Professor Michael Tarbutt and Professor Edward Hinds, both at Imperial College London, to build advanced instrumentation capable of detecting new fundamental particles through precision measurement of the distortions these particles cause to the distribution of electric charge in an electron.К Tarbutt and HindsХs primary detection strategy is to use intersecting lasers to create an electromagnetic ТlatticeУ that holds diatomic molecules at a fixed point in space. The held molecules can then be measured for perturbations in their electrical charge. The approach, called optical trapping, has significant theoretical advantages over other methods. First, optical traps can hold neutral molecules and neutral molecules can be packed very denselyСcharged particles disrupt one another when they are too close togetherСallowing for more measurements to be made per unit of space. Second, holding molecules still, as optical trapping does, allows the molecules to be measured for thousands of times longer than efforts using molecules in motion. The technical challenge is that only very cold molecules can be caught in an optical trap. Tarbutt and HindsХs primary activities over the grant period will be to see if ytterbium fluoride (YbF) molecules can be cooled to the microkelvin temperatures needed to make them candidates for optical trapping. They plan to bring YbF molecules into collision with a super-cold cryogenic buffer gas, which will cool the molecules sufficiently to allow laser-based techniques to take over and cool the molecules to the appropriate temperature. If successful, this would put the team in position to improve existing detection methods by a factor of 1,000, representing a significant leap in detection technology. The project will produce several papers on laser slowing and cooling of an EDM relevant molecule, as well as training for two postdoctoral and two graduate students.