Browsing by Author "Liu, Z. W."

Now showing 1 - 4 of 4
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    Characterizing ultrashort optical pulses using second-order nonlinear nanoprobes
    Li, H. F.; Zhang, Z.; Xu, Q. A.; Shi, K. B.; Jia, Y. S.; Zhang, B. G.; Xu, Yong; Liu, Z. W. (AIP Publishing, 2010-12-01)
    We report a second-order nonlinear nanoprobe for characterizing ultrafast optical near fields. The proposed nanoprobe comprises second harmonic nanocrystals attached to a carbon nanotube, which is in turn attached to a silica fiber taper. We demonstrate in situ pulse characterization directly in the air core of a photonic crystal fiber. Further, it is shown that nanoprobes containing a single nanocrystal in the tip of the nanotube can be fabricated by auxiliary focused ion beam nanomilling. These results indicate that the proposed nanoprobe can open an avenue for probing the evolution of ultrafast optical fields in complex three-dimensional micro-or nanostructures. (C) 2010 American Institute of Physics. [doi:10.1063/1.3532112]
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    Demonstration Of A Cylindrically Symmetric Second-Order Nonlinear Fiber with Self-Assembled Organic Surface Layers
    Daengngam, Chalongrat; Hofmann, M.; Liu, Z. W.; Wang, Anbo; Heflin, James R.; Xu, Yong (Optical Society of America, 2011-05-01)
    We report the fabrication and characterization of a cylindrically symmetric fiber structure that possesses significant and thermodynamically stable second-order nonlinearity. Such fiber structure is produced through nanoscale self-assembly of nonlinear molecules on a silica fiber taper and possesses full rotational symmetry. Despite its highly symmetric configuration, we observed significant second harmonic generation (SHG) and obtained good agreement between experimental results and theoretical predictions. (C) 2011 Optical Society of America
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    Development of a nonlinear nanoprobe for interferometric autocorrelation based characterization of ultrashort optical pulses
    Li, H. F.; Jia, Y. S.; Xu, Q.; Shi, K. B.; Wu, J.; Eklund, P. C.; Xu, Yong; Liu, Z. W. (AIP Publishing, 2010-01-01)
    Near-field scanning can achieve nanoscale resolution while ultrashort pulse diagnostic tools can characterize femtosecond pulses. Yet currently it is still challenging to nonperturbatively characterize the near field of an ultrashort optical pulse with nanofemtoscale spatiotemporal resolution. To address this challenge, we propose to develop a nonlinear nanoprobe composed of a silica fiber taper, a nanowire, and nonlinear fluorescent spheres. Using such a nanoprobe, we also report proof-of-principle characterization of femtosecond optical pulse through interferometric autocorrelation measurement.
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    Proposal and analysis of a silica fiber with large and thermodynamically stable second order nonlinearity
    Xu, Yong; Wang, Anbo; Heflin, James R.; Liu, Z. W. (AIP Publishing, 2007-05-01)
    The authors propose a general approach that can produce a silica fiber with large and thermodynamically stable second order nonlinearity. They estimate that it is possible to achieve second harmonic generation efficiency of more than 10% in such a nonlinear fiber with a length of a few hundred microns. By maintaining a high degree of spatial symmetry, the proposed nonlinear fiber can naturally generate polarization entangled photon pairs, a physical object of enormous significance for quantum information technology. (c) 2007 American Institute of Physics.