Joel A Greenberg, Entered 2005/06  

Joel A Greenberg

Office Location: 183 Physics
Office Phone: 919-660-2512
Email Address: jag27@phy.duke.edu
Web Page: http://www.phy.duke.edu/~jag27/projects.html

Specialties:
Atomic, molecular, and optical physics
Nonlinear dynamics and complex systems

Education:
M.A., Duke University, 2008
BSE, Princeton University, 2005

Research Categories: Quantum Optics, Nonlinear Optics, Cold Atoms

Research Description: I am interested in studying nonlinear optics at low light levels. Because the nonlinear response of a material is typically very small, large intensities (i.e., large numbers of photons) are needed to see significant nonlinear effects. In my research, I am investigating ways to enhance the material's nonlinear susceptibility by coherently modifying its properties. Specifically, I use an anisotropic magneto-optical trap (MOT) to produce a sample of mico-Kelvin temperature atoms confined to a small, cigar-shaped region of space. These cold atoms act as my nonlinear medium; by applying additional magnetic and optical fields, I study and alter their nonlinear response.

My current work focuses on a phenomenon known as recoil-induced resonances (RIRs), whereby a two-photon Raman scattering process coherently couples atomic momentum states. In addition to providing large gain/absorption with relatively small incident probe powers (~20pW),  the fact that the atoms recoil gives rise to atomic bunching in the spatial domain.  This bunching can result in collective radiation from the sample, giving superlinear scaling with atomic number.  I am currently studying the transition from single to collective effects in our MOT.

Another interseting feature of the RIRs is the inhomogeneously broadened nature of the atoms, which allows for the selection and manipulation of individual momentum states.  This allows us to tailor the gain profile of the atomic sample via momentum state engineering.  Also, by individually addressing momentum states, classical information storage via holeburning or  quantum information storage via photon echo techniques are possible.  I am currently investigating the feasibility of these techniques.

Teaching (Fall 2009):   (typical courses)

  • Physics 265, Advanced optics
    This course presents a rigorous treatment of topics in Photonics and Optics targeted at students with an existing photonics or optics background. Topics will include, Optical Sources, Statistical Optics and Coherence Theory, Detection of Radiation; Nonlinear Optics; Waveguides and Optical Fibers; Modern Optical Modulators; Ultrafast lasers and Applications.
  • Phy 265, Advanced optics

Recent Publications

  1. J.A. Greenberg and D.J. Gauthier, Transient dynamics and momentum redistribution in cold atoms via recoil-induced resonances, Phys. Rev. A (2009)  [abs].
  2. A.M.C. Dawes, L. Illing, J.A. Greenberg, D.J. Gauthier, All-Optical Switching with Transverse Optical Patterns, Phys. Rev. A, vol. 77 (2008), pp. 013833  [abs].
  3. J. A. Greenberg, M. Oria, A. M. C. Dawes, and D. J. Gauthier, Absorption-induced trapping in an anisotropic magneto-opticla trap, Optics Express, vol. 15 (2007), pp. 17699  [abs].
  4. Dunaevsky, A. Goltsov, J. Greenberg, E. Valeo, N. J. Fisch, Formation of laser plasma channels in a stationary gas, Phys. Plasmas, vol. 13 (2006), pp. 043106  [abs].

Curriculum Vitae

Highlight:
I am interested in studying nonlinear optics at low light levels. Because the nonlinear response of a material is typically very small, large intensities (i.e., large numbers of photons) are needed to see significant nonlinear effects. In my research, I am investigating ways to enhance the material's nonlinear susceptibility by coherently modifying its properties.

Selected Talks

  1. Superradiance in an ultracold thermal vapor, July 15, 2009, OSA NLO (Honolulu, HI)    
  2. Transient enhancement of the nonlinear atom-photon coupling via recoil-induced resonances, May 22, 2009, DAMOP (Charlottesville, VA)    
  3. Investigation of the Saturation Mechanism of Recoil-induced Resonances, July, 2008, DAMOP (State College, PA)    
Selected Other

  1. Momentum-state Engineering via Recoil-Induced Resonances, September, 2008, Poster presented at annual Fitzpatrick Insitute of Photonics meeting (Duke University, NC)    
  2. Nonlinear Beam Shaping in an Anisotropic Magneto-optical Trap, July, 2008, Poster presented at DAMOP (State College, PA)    
  3. Anisotropic MOT for Nonlinear Optical Studies, September, 2007, Poster presented at annual Fitzpatrick Insitute of Photonics meeting (Duke University, NC)    
  4. Anisotropic MOT for Nonlinear Optical Studies, July, 2007, Poster Presented at Atomic Physics Gordon Conference (Tilton School, NH)    
  5. Theoretical Optimization of a DAVLL System in Rubidium Vapor, September, 2006, Poster presented at annual Fitzpatrick Insitute of Photonics meeting (Duke University, NC)    
  6. Determining the ANCs for 13C 12C+n for Nuclear Astrophysics Studies, October, 2004, Poster Presented at APS DNP meeting (Chicago, IL)