Our quantum systems explore the frontiers of control in atomic, optical, and mesoscopic physics. We laser cool the vibrations of mechanical objects that can measure displacements and extremely small forces at quantum limits. We are able to entangle and interfere single atoms placed atom-by-atom in identical quantum states. Our work enables transduction between disparate quantum systems and exploration of quantum many-body physics.
Laser cooling of atoms uses radiation forces of light to push on atoms, and has revolutionized atomic physics. In our work, in a field known as optomechanics, we now have the capacity to cool vibrations of mesoscopic objects using radiation pressure combined with cryogenic cooling. We pick out particular nanomechanical modes of the solid that are well-isolated from their environment, and that we can control with light using an extremely-precise optical cavity.
We are studying a quantum system of bosonic 87Rb atoms in optical tweezers assembled particle-by-particle. We have shown optical tweezers can be used to confine atoms sufficiently to place them in their motional ground state via Raman sideband laser cooling. With this ability, we make bosonic atoms indistinguishable in all but their positional degree of freedom, and we can interfer two atoms to see the analog of the Hong-Ou-Mandel effect with atoms.
Electro-optic devices are ubiquitous in classical optical systems. In the quantum domain, an electro-optic device would also be very handy, for example, to transduce states created with superconducting quantum bits (qubits) to optical light. However, at the moment no electro-optic component exists that is low enough noise and efficient enough to work with quantum states.