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Research
Generation of Scalable Quantum Entanglement
The generation and study of scalable quantum entanglement is one of the grand challenges of modern physics. We have been working towards this goal, using the many-body physics of Bose-Einstein condensates to prepare atomic number states as the building block for entanglement. We have developed a unique system that includes a tightly confined condensate in a 1-D box potential, providing an experimental realization of the "particle in a box." We have also developed sensitive detection that can resolve a single atom with nearly unit efficiency. We will use this system to study the control of a many body system. We have recently succeeded in generating atomic number squeezing and our results are consistent with the production of atomic many-body number states. These results are also in agreement with a recent theoretical analysis that we performed. Atomic number states are the building block for controlled study of quantum entanglement, few-body tunneling, and quantum computing. The methods of atom counting should also enable a first statistical study of quantum critical phenomena.
Comprehensive Control of Atomic and Molecular Motion
We have been working to develop new methods of cooling and trapping that are applicable to any atom or molecule, a result of far-reaching significance for physics and chemistry. The starting point for our work is the supersonic molecular beam which is an important tool in Physical Chemistry. In collaboration with Professor Uzi Even, a Chemist from Tel-Aviv University, we are using a unique valve that he developed and which provides a pulse duration as short as 10 microseconds combined with cryogenic operation. This serves as a universal platform for cold but fast atoms and molecules that are seeded or entrained into the supersonic flow. We proposed that a series of pulsed magnetic field coils could stop and trap any paramagnetic species. This "atomic coilgun" was inspired by the coilgun which is used to launch large projectiles. We reported the first experimental slowing of metastable neon atoms in Fall 2007 and have now completely stopped the beam. Atoms and molecules that are magnetically trapped can be further cooled with a new method that we developed based on a "one-way wall of light." We have also developed a method to slow atoms or molecules that do not have a magnetic moment using elastic reflection from a single crystal that is mounted on a spinning rotor. We have demonstrated coherent slowing of ground-state helium. This work opens a new field of "crystal atom optics." We are investigating the possible construction of an atomic interferometer based on a single crystal with potential important applications for inertial sensing.
Trapping of Atomic Hydrogen Isotopes
We will apply the methods described above to trapping and cooling of atomic hydrogen isotopes. Atomic hydrogen has been the "Rosetta Stone" of physics for many years and is the simplest and most abundant atom in the universe. The two isotopes of hydrogen are deuterium with one neutron, and tritium with two neutrons. Precision spectroscopy of these isotopes continues to be of great interest to atomic physics and nuclear physics. Tritium is the simplest radioactive element and serves as an ideal system for the study of beta decay. The latter may be the only way to determine the electron neutrino rest mass, one of the most pressing questions in physics and astronomy. Despite these very important features, hydrogen has remained very difficult to control and trap while deuterium and tritium have never been trapped. The first stage of our research will concentrate on trapping of hydrogen and deuterium where precision spectroscopy will be performed. This work will serve as a natural stepping stone to trapping of atomic tritium and an experiment to determine the neutrino rest mass.
[ Raizen Group| Center for Nonlinear Dynamics | Department of Physics | UT Austin ] |