Older Publications (2003 - 2008)

September 4, 2008

Broadband supercontinuum generation covering UV to mid-IR region by using three pumping sources in single crystal sapphire fiber

Jae Hun Kim, Meng-Ku Chen, Chia-En Yang, Jon Lee, Kebin Shi, Zhiwen Liu, Stuart (Shizhuo) Yin, Karl Reichard, Paul Ruffin, Eugene Edwards, Christina Brantley, and Claire Luo, Optics Express 16, 14792-14800 (2008).

In this paper, we demonstrate that the the bandwidth of the supercontinuum spectrum generated in a large mode area sapphire fiber can be enhanced by employing triple pumping sources. Three pumping sources with wavelengths of 784nm, 1290nm, and 2000nm are launched into a single crystal sapphire fiber that is 5cm in length and has a core diameter of 115µm. The nonlinear interactions due to self-phase modulation and four-wave mixing form a broadband supercontinuum that covers the UV, visible, near-IR and lower mid-IR regions. Furthermore, we explore the possibility of generating a broadband supercontinuum expanding from the UV to far-IR region by increasing the number of pumping sources with wavelengths in the mid- and far-IR.

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March 31, 2008

Spectrally smoothed supercontinuum generation by using unstably mode-locked laser pulses

Kebin Shi and Zhiwen Liu, Appl. Phys. Lett. 92, 131102 (2008).

We report on a simple approach to obtain spectrally smoothed supercontinuum (SC) by using unstably mode-locked femtosecond laser pulses. The spectrum smoothing effect is due to the averaging of the supercontinua generated in a nonlinear photonic crystal fiber by modulated pulses. Theoretical analysis based upon solving the generalized nonlinear Schrödinger equation is presented, which qualitatively agrees well with the experimental observation. Finally, the application of the smoothed SC to broadband coherent anti-Stokes Raman scattering spectroscopy is demonstrated, which can result in a relatively smooth nonresonant background and suppress spurious peaks.

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May 27, 2008

Long-path supercontinuum absorption spectroscopy for measurement of atmospheric constituents

David M. Brown, Kebin Shi, Zhiwen Liu, and C. Russell Philbrick, Optics Express 16, 8457-8471 (2008).

A supercontinuum source has been proposed as a new tool for measurement of minor species concentrations on long paths through the atmosphere. The present work describes results from recent experiments that demonstrate the potential for Differential Absorption Spectroscopy (DAS) and Spectral Pattern Recognition Differential Absorption Lidar (SPR-DIAL) measurements utilizing a supercontinuum source. As an initial example of this measurement approach, the results include the quantification of water vapor concentration through indoor and outdoor path absorption measurements using a collimated supercontinuum source. Experimental spectra are compared with equivalent simulations from MODTRAN™ versions 4 and 5 to examine the water vapor band between 1300 and 1500 nm to emonstrate the feasibility of the approach.

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Y. Xu, M. Han, A. Wang, Z. Liu, and J.R. Heflin, “Second Order Parametric Processes in Nonlinear Silica Microspheres,” Physical Review Letters 100, 163905 (2008).

M. O. Ramirez, J. Wisdom, H. Li, Y. L. Aung, J. Stitt, G. L. Messing, V. Dierolf, Z. Liu, A. Ikesue, R. L. Byer, and V. Gopalan, "Three-dimensional grain boundary spectroscopy in transparent high power ceramic laser materials," Optics Express 16, 5965-5973 (2008).


Y. Xu, A. Wang, J. R. Heflin, and Z. Liu, “Proposal and analysis of a silica fiber with large and thermodynamically stable second order nonlinearity,” Applied Physics Letters 90, 211110 (2007).

Kebin Shi, Peng Li, and Zhiwen Liu, "Supercontinuum Cars Tweezers," Journal of Nonlinear Optical Physics & Materials 16, 457-470 (2007).

Y. Xu, A. Wang, J. R. Heflin, and Z. Liu, “Proposal and analysis of a silica fiber with large and thermodynamically stable second order nonlinearity,” Applied Physics Letters 90, 211110 (2007).

Kebin Shi, Peng Li, and Zhiwen Liu, "Broadband Coherent Anti-Stokes Raman Scattering Spectroscopy in Supercontinuum Optical Trap," Applied Physics Letters 90, 3 (2007).

Matthew E. Staymates, Gary S. Settles, Kebin Shi, and Zhiwen Liu, "Supercontinuum Laser Illumination Applied to Traditional Optical Flow Imaging Methods," Optics Communications 273, 252-255 (2007).


Kebin Shi, Fiorenzo G. Omenetto, and Zhiwen Liu, "Supercontinuum Generation in an Imaging Fiber Taper," Optics Express 14, 12359-12364 (2006).

Kebin Shi, Shizhuo Yin, and Zhiwen Liu, "Wavelength Division Scanning for Two-Photon Excitation Fluorescence Imaging," Journal of Microscopy-Oxford 223, 83-87 (2006).

Kebin Shi, Ahmed A. Heikal, and Zhiwen Liu, "A Single-Shot Approach for Measuring Two-Photon Action Cross-Section of Fluorescent Markers," Optics Express 14, 8722-8727 (2006).

Kebin Shi, Sung Hyun Nam, Peng Li, Shizhuo Yin, and Zhiwen Liu, "Wavelength Division Multiplexed Confocal Microscopy Using Supercontinuum," Optics Communications 263, 156-162 (2006).

Fei Wu, Xueqian Zhang, Joseph Y Cheung, Kebin Shi, Zhiwen Liu, Claire Luo, Stuart Yin, Paul Ruffin, "Frequency Division Multiplexed Multichannel High-Speed Fluorescence Confocal Microscope," Biophysical Journal 91, 2290-2296 (2006).


Peng Li, Kebin Shi, Zhiwen Liu ,"Optical scattering spectroscopy by using tightly focused supercontinuum,"Optics Express 13, 9039-9044 (2005).

Wei-Hung Su, Kebin Shi, Zhiwen Liu, Bo Wang, Karl Reichard, Shizhuo Yin, "A large-depth-of-field projected fringe profilometry using supercontinuum light illumination," Optics Express 13, 1025-1032 (2005).

Peng Li, Kebin Shi, Zhiwen Liu ," Manipulation and spectroscopy of a single particle by use of white-light optical tweezers ," Optics Letters 30, 156-158 (2005).


Yi Yang, Kunwook Chung, Shizhuo Yin, Zhiwen Liu, and Qing Wang,"Analysis of volume holographic long period gratings in photonic nanostructured fibers and waveguides," Optical Engineering 43, 2003-2008 (2004).

K. Shi, P. Li, S. Yin, and Z. Liu, "Chromatic confocal microscopy using supercontinuum light, "Optics Express 12, 2096-2101(2004).

M. Centurion, Y. Pu, Z. Liu, D. Psaltis, and T.W. Hansch, "Holographic recording of laser-induced plasma,"Optics Letters 29, 772- 774(2004).

The Pennsylvania State University    Department of Electrical Engineering