RESEARCH INTERESTS

Quantum Information Processing

One of the great successes of quantum physics which is the long-lived Rydberg states of donor and acceptor impurities in silicon. Of particular interest because they can be exploited for quantum control of one atom by another are excited Rydberg states, where wavefunctions are expanded from their ground state extents of below 0.1 nm to several nm and even beyond; this allows atoms far enough apart to be noninteracting in their ground states to strongly interact in their excited states. For eventual application, a solid state implementation is very desirable, and we demonstrated the coherent control of impurity wavefunctions in the most ubiquitous donors and acceptors in a semiconductor, namely the phosphorous- and boron-doped silicon. Our experiments take advantage of a free-electron laser to stimulate and observe population times, photon echoes, the orbital analog of the Hahn spin echo, Rabi oscillations.