George Michael Gehring, Ph.D.

George Michael Gehring
Assistant Teaching Professor of Physics, School of Science, Engineering, and Technology
Office Phone
Office Location
Science & Technology Building, 126TL
8:30 a.m. - 5:00 p.m.
126TL Science & Tech Bldg
Penn State Hbg
Middletown, PA 17057

Dr. George Gehring earned his Ph.D. in Optics from the University of Rochester. He has been teaching at the undergraduate level since 2012, and has been a faculty member at Penn State Harrisburg since 2017. He is a member of the Optical Society of America (OSA), American Physical Society (APS), and American Association of Physics Teachers (AAPT), and serves as advisor to both the Penn State Harrisburg Astronomy Club and E-Sports Club.

His research in nonlinear optics investigated two different aspects of pulse propagation dynamics. He investigated slow and fast light systems, particularly looking at negative group velocities and "backwards" light in erbium fiber amplifiers. Another focus of his research was single-photon quantum-mechanical barrier tunneling and delay times, and the direct analogs between the classical electrodynamics of total internal reflection and the quantum mechanics of one-dimensional barrier tunneling. More recently, he has become interested in using 3-D printing to create more affordable alternatives to common optomechanical devices for undergraduate teaching and research laboratory purposes.

Research Interests

Nonlinear Optics

Slow and Fast Light Propagation

Quantum-Mechanical Barrier Tunneling

Evanescent Cavity Electrodynamics

Total Internal Reflection

Optical Interactions in Liquid Crystals

Optical Metamaterials and Negative-Index Materials

3-D Printing for Optomechanics and Optical Materials


S. G. Lukishova, A. C. Liapis, L. J. Bissel, G. M. Gehring, and R. W. Boyd, “Single-photon experiments with liquid crystals for quantum science and quantum engineering applications,” Liquid Crystal Reviews 2, 111 (2014).

G. M. Gehring, A. C. Liapis, S. G. Lukishova, and R. W. Boyd, “Time-Domain Measurements of Single-Photon Tunneling Phenomena,” Phys. Rev. Lett 111, 030404 (2013).

G. M. Gehring, A. C. Liapis, and R. W. Boyd, “Tunneling delays in frustrated total internal reflection,” Phys. Rev. A 85, 032122 (2012).

G. M. Gehring, H. Shin, R. W. Boyd, C. M. Kim, and B. S. Ham, “Tunable optical time delay of quantum signals using a prism pair,” Optics Express 18, 19156 (2010).

G. M. Gehring, R. W. Boyd, A. L. Gaeta, D. J. Gauthier, and A. E. Willner, “Fiber-Based Slow-Light Technologies,” Journal of Lightwave Technology, 26, 3752 (2008).

H. Shin, A. Schweinsberg, G. Gehring, K. Schwertz, H. J. Chang, and R. W. Boyd, “Reducing pulse distortion in fast-light pulse propagation through an erbium-doped fiber amplifier,” Optics Letters 32, 906 (2007).

D. D. Smith, N. N. Lepeshkin, A. Schweinsberg, G. Gehring, and R. W. Boyd, “Coupled-resonator-induced transparency in a fiber system,” Optics Communications 264, 163 (2006).

G. M. Gehring, A. Schweinsberg, C. Barsi, N. Kostinski, and R. W. Boyd, “Observation of Backwards Pulse Propagation Through a Medium with a Negative Group Velocity,” Science 312, 895 (2006).

"Using artificial intelligence to grade faster and improve feedback," 2019 Symposium for Teaching and Learning with Technology, Penn State University, March 16, 2019.

"Just Let the Robots Handle It: Using AI to Speed Up Grading and Provide Immediate Feedback to students," PSU Physics Meeting, Physics Department, PSU Lehigh Valley October 10, 2018.

"Just Let the Robots Handle It: Using AI to Speed Up Grading and Provide Immediate Feedback to students," Faculty Spotlight, Center for Teaching Excellence, PSU Harrisburg, September 18, 2018.

“Single-Photon Tunneling Delay in a Nematic Liquid-Crystal Frustrated-Total-Internal-Reflection Structure,” Quantum Electronics and Laser Science (QELS), QThN6, Baltimore, MD, May 2011.

“Superluminal Optical Effects,” UR/uOttawa Research Workshop, Ottawa, Ontario Canada, November 2010.

“Fiber-Based Slow Light Technologies,” Photons After Dark (graduate student-run colloquium series), Rochester, NY, July 2007.

“Backwards Pulse Propagation in Erbium Doped Fiber,” Conference on Coherence and Quantum Optics (CQO), CSuA, Rochester, NY, June 2007.

“Pulse Propagation with a Negative Group Velocity in Erbium Doped Fiber,” OSA Frontiers in Optics (FiO), FThG, Rochester, NY, October 2006.

“Backwards Pulse Propagation with a Negative Group Velocity in Erbium Doped Fiber,” OSA Slow and Fast Light (SL), WA2, Washington, DC, July 2006.

“Observation of Exotic Pulse Propagation in Erbium-Doped Optical Fibers,” Conference on Lasers and Electro-Optics (CLEO), CThW, Long Beach, CA, May 2006.


Ph.D. Optics, University of Rochester 2012

B.S. Physics, Juniata College 2003

Course Schedule
PHYS 211