Harris Research Group

Ginzton Laboratory

Stanford University

Description of Research

Electromagnetically induced transparency (EIT) is a technique for eliminating the effect of a medium on a propagating beam of electromagnetic radiation.  EIT may also be used to eliminate optical self-focusing and to improve the transmission of laser beams through inhomogeneous refracting gases and metal vapors.  Of particular interest to our group, EIT may also be used to create large populations of coherently-driven, uniformly-phased atoms, thereby making possible new types of optical frequency converters and oscillators.

Present projects are: (1) the use of EIT to cause light to propagate as slow as 10 m/s and to demonstrate nonlinear optical effects at nW power levels;  (2) paired single photon generation with prescribed temporal shapes and individual coherence lengths measured in meters, thus allowing for a new class of single-photon experiments dependent upon long coherence lengths; and (3) producing a comb of Raman sidebands that span a bandwidth of almost four octaves.  By taking seven of these sidebands and adjusting their relative phases, we have formed a single-cycle, 1.6 fs optical pulse.  We are currently improving the source to generate Raman sidebands within a hollow fiber. (4) We are in the early phases of a new project whose objective is the experimental demonstration of the generation of paired time-energy entangled photons that have a temporal length of a single cycle.

Group Members