Subir Kumar Roy

Professor

E-mail:        spskr [ AT ] iacs.res.in
Fax:           +91 33 2473 2805
Telephone: +91 33 2473 4971 ext 355

Born on 29th February, 1948
Ph. D in Science (Physics) 1980

Post-Doctoral and other Professional Experiences:

(I) Visiting Research Associate , Department of Chemistry, University of Sheffield, UK, during,1989 to 1991.
(II) Visiting Scientist under German Academic Exchange Service (DAAD) during November,1995 to February 1996 , Department of Physical Chemistry, Technical University , Darmstadt, Germany.
(III) Visiting Scientist under DLR during August to September,1999. Department of Physical Chemistry , Technical University ,Darmstadt, Germany
 

Research Interest:

Liquid Crystals and Polymeric Liquid Crystals:
Electro-optic and Dielectric properties , Dielectric Relaxation Spectroscopy , FTIR spectroscopy and X-ray studies
 

Representative list of Publications:


* Electro-optic effect and influence of bias electric field on the Goldstone mode dielectric behavior in Sm C* phase and cell thickness dependence of the dielectric permittivity of a ferroelectric liquid crystal mixture. S. Sinha Roy, S. Kundu, N. Ghosh, T. Pal Majumder and S. K. Roy, Mol. Cryst. Liq. Cryst. Vol. 328, pp. 161-176, 1999.

* Mesomorphic properties and orientational Order Parameter of 4 - Pentyl Cyclohexyl - 4 -(4 - Propyl cyclohexyl) benzoate from X- ray diffraction studies, Anuradha mukhopadhyay, Golam Mostafa, Siddhartha Ray and S. K. Roy, Phase Transitions, Vol. 68, pp. 383-397, 1999.

* Effect of Spontaneous Polarization on smectic C*- smectic A* phase transition temperature and cell thickness dependence of the spontaneous polarization of ferroelectric liquid crystal, S. Sinha Roy, T., Pal majumder, P. K. Mukherjee and S. K. Roy, Liquid Crystal, 25, 59, 1998.

* Studies on the dielectric behaviour of TGBA phases, . S. K. Roy, S.Hiller, J. W. Goodby, and W. Haase, Ferroelectrics, Vol. 200, pp. 65-80, 1997.

* Soft mode Dielectric relaxation under the influence of bias electric field of a FLC mixture, S. Sinha Roy. T. Pal majumder. and S. K. Roy, Mol. Cryst. Liq. Cryst., Vol. 304, pp. 315-320, 1997.

* Behavior of the Goldstone mode in Smectic- C* phase and soft mode in the smectic C* and smectic-A* phases of a ferroelectric liquid-crystal mixture , T. Pal Majumder, S. Sinha Roy and
S. K. Roy, Phy Rev E , vol 54(2), 2150, 1996.

* Dielectric relaxation and rotational viscosity of a ferroelectric liquid crystal mixture T. Pal Majumder, M. Mitra and S. K. Roy, Phys. Rev. E, 50,4796, 1994.