Research Interests

The use of light scattering, magneto-optics, electro-optics, and electron diffraction to study phase transitions and critical phenomena in liquid crystals, biomembranes and microemulsions.

Some of the recent results of his work include:

  • The discovery of unusual properties including anomalous light scattering and correlations between the orientational elasticity and short-range positional order near the nematic-smectic-A-smectic-C multicritical point in binary liquid- crystal mixtures.
  • The first application of electron diffraction to study the bond-orientational order in thin free-standing liquid-crystal films to obtain information about the scaling of the higher harmonic order parameters, and to provide the first confirmation of the existence of a hexatic phase as predicted by the theory of defect-mediated melting in two dimensions.
  • The discovery of some unique layer by layer surface-freezing and orientational epitaxy phenomena on the surface of hexatic liquid crystals undergoing phase transitions.

Selected Publications

  • "New Hexatic Liquid Phase Observed in Lyotropic Thin Films", C. Y. Chao, M. T. Hsu, W. J. Hsieh, J. T. Ho, and I. J. B. Lin, Phys. Rev. Lett. 93, 247801 (2004).
  • "Multiple Electron Diffraction and Two-Dimensional Crystalline Order in Liquid-Crystal Thin Films", C. Y. Chao, T. C. Pan, C. F. Chou, and J. T. Ho, Phys. Rev. Lett. 91, 125504 (2003).
  • "Unusual Thickness-Dependent Heat-Capacity Anomalies in Free-Standing Hexatic Liquid-Crystal Films", C. Y. Chao, C. R. Lo, P. J. Wu, T. C. Pan, M. Veum, C. C. Huang, V. Surendranath, and J. T. Ho, Phy. Rev. Lett. 88, 085507 (2002).
  • "Unusual Thickness-Dependent Behavior and Anticlinic Coupling in Chiral Smectic Liquid-Crystal Films", C. Y. Chao, C. R. Lo, P. J. Wu, Y. H. Liu, D. R. Link, J. E. Maclennan, N. A. Clark, M. Veum, C. C. Huang, and J. T. Ho, Phys. Rev. Lett. 86, 4048 (2001).
  • "Light Scattering and Quasielastic Spectroscopy", J. T. Ho, in "Liquid Crystals: Experimental Study of Physical Properties and Phase Transitions", edited by S. Kumar (Cambridge University Press, Cambridge, 2001), pp. 197-239.
  • "Multiple-Step Melting in Two-Dimensional Liquid-Crystal Films", C. F. Chou, A. J. Jin, S. W. Hui, C. C. Huang, and J. T. Ho, Science 280, 1424 (1998).
  • "Layer-Dependent Surface-Induced Tilt, Hexatic and Positional Orders in Free-Standing 7O.7 Films", C. Y. Chao, S. W. Hui, and J. T. Ho, Phys. Rev. Lett. 78, 4962 (1997).
  • "Surface-Freezing Transitions and Novel Tilted Hexatic Phases in Smectic Liquid-Crystal Films", C. Y. Chao, S. W. Hui, J. E. Maclennan, C. F. Chou, and J. T. Ho, Phys. Rev. Lett. 78, 2581 (1997).
  • "Nature of Layer-by-Layer Freezing in Free-Standing 4O.8 Films", C. Y. Chao, C. F. Chou, J. T. Ho, S. W. Hui, A. J. Jin, and C. C. Huang, Phys. Rev. Lett. 77, 2750 (1996).
  • "Scaling of 6n-Fold Bond-Orientational Order Parameters in a Hexatic Liquid-Crystal Thin Film", C. F. Chou, J. T. Ho, S. W. Hui, and V. Surendranath, Phys. Rev. Lett. 76, 4556 (1996).
  • "Calorimetric and Structural Characterization of Thin Liquid-Crystal Films Exhibiting the Smectic-A-Hexatic-B-Crystal-B Transition", A. J. Jin, M. Veum, T. Stoebe, C. F. Chou, J. T. Ho, S. W. Hui, V. Surrendranath, and C. C. Huang, Phys. Rev. Lett. 74, 4863 (1995).
  • "Liquid-Hexatic Phase Transitions in Single Molecular Layers of Liquid-Crystal Films", R. Greer, T. Stoebe, C. C. Huang, R. Pindak, J. W. Goodby, M. Cheng, J. T. Ho, and S. W. Hui, Nature 355, 152 (1992).
  • "Hexatic and Crystal Phase Transitions in Thin Free-Standing Liquid-Crystal Films", R. Geer, T. Stoebe, C. C. Huang, R. Pindak, G. Srajer, J. W. Goodby, M. Cheng, J. T. Ho, and S. W. Hui, Phys. Rev. Lett. 66, 1322 (1991).
  • "Dynamics of Director Fluctuations near the Nematic-Smectic-A-Smectic-C Multicritical Point", R. Qiu and J. T. Ho, Phys. Rev. Lett. 64, 1122 (1990).
  • "Observation of Two-Dimensional Hexatic Behavior in Free-Standing Liquid-Crystal Thin Films", M. Cheng, J. T. Ho, S. W. Hui, and R. Pindak, Phys. Rev. Lett. 61, 550 (1988).
  • "Reply to Harmonics of Orientational Order in Liquid Crystals", M. Cheng, J. T. Ho, S. W. Hui, and R. Pindak, Phys. Rev. Lett. 60, 862 (1988).
  • "Electron-Diffraction Study of Free-Standing Liquid-Crystal Films", M. Cheng, J. T. Ho, S. W. Hui, and R. Pindak, Phys. Rev. Lett. 59, 1112 (1987).
  • "Behavior of Bend Elastic Constant near the Nematic-Smectic-A-Smectic-C Multicritical Point", J. Huang and J. T. Ho, Phys. Rev. Lett. 58, 2239 (1987).
  • "Critical Scattering", J. T. Ho, in "Encyclopedia of Materials Science and Engineering", edited by M. B. Bever (Pergamon, London, 1986), p. 953.
  • "Light Scattering above the Nematic-to-Smectic-C Transition", S. Witanachchi, J. Huang, and J. T. Ho, Phys. Rev. Lett. 50, 594 (1983).
  • "Reversibility of Sodium-Induced Aggregation of Sonicated Phosphatidylserine Vesicles", E. P. Day, A. Y. W. Kwok, S. K. Hark, J. T. Ho, J. Vail, J. Bentz, and S. Nir, Proc. Natl. Acad. Sci. USA 77, 4026 (1980).
  • "Pretransitional Behavior of Birefringence in a Smectic-B Liquid Crystal near the Smectic-A Phase", K. C. Lim and J. T. Ho, Phys. Rev. Lett. 43, 1167 (1979).
  • "Critical Suppression of Birefringence in a Smectic-A Liquid Crystal near the Smectic-C Phase", K. C. Lim and J. T. Ho, Phys. Rev. Lett. 40, 1576 (1978).
  • "Temperature Dependence of Calcium-Induced Fusion of Sonicated Phosphatidylserine Vesicles", S. T. Sun, E. P. Day, and J. T. Ho, Proc. Natl. Acad. Sci. USA 75, 4325 (1978).
  • "Coupling between Orientational and Translational Order in a Liquid Crystal", K. C. Lim and J. T. Ho, Phys. Rev. Lett. 40, 944 (1978).
  • "Dynamics of Fréedericksz Deformation near a Nematic-Smectic-A Transition", C. C. Huang, R. S. Pindak, P. J. Flanders, and J. T. Ho, Phys. Rev. Lett. 33, 400 (1974).
  • "Divergence of Cholesteric Pitch near a Smectic-A Transition", R. S. Pindak, C. C. Huang, and J. T. Ho, Phys. Rev. Lett. 32, 43 (1974).
  • "Correlation between Magnetization and Field-Dependent Specific-Heat Data near the Critical Point", J. T. Ho, Phys. Rev. Lett. 26, 1485 (1971).
  • "Correlation between Critical Coefficients and Critical Exponents", P. Schofield, J. D. Litster, and J. T. Ho, Phys. Rev. Lett. 23, 1098 (1969).
  • "Magnetic Equation of State of CrBr3 near the Critical Point", J. T. Ho and J. D. Litster, Phys. Rev. Lett. 22, 603 (1969).