Cochin University of Science and Technology

About: Cochin University of Science and Technology is a education organization based out in Kochi, Kerala, India. It is known for research contribution in the topics: Thin film & Natural rubber. The organization has 5382 authors who have published 7690 publications receiving 103827 citations. The organization is also known as: CUSAT & Cochin University.

Thermodynamics and Thermodynamic geometry of Park black hole

Abstract: We study the thermodynamics and thermodynamic geometry of Park black hole in Ho rava gravity. By incorporating the ideas of dierential geometry, we have investigated the thermodynamics using Weinhold geometry and Ruppeiner geometry. We have also analyzed it in the context of newly developed geometrothermodynamics(GTD). Divergence of specic heat is associated with the second order phase transition of black hole. Here in the context of Park black hole, both Weinhold’s metric and Ruppeiner’s metric well explain this phase transition. But these explanations depend on the choice of potential. Hence the Legendre invariant GTD is used, and with the true singularities in the curvature scalar, GTD well explain the second order phase transition. All these methods together give an exact idea of all the behaviors of the Park black hole thermodynamics.

The Effect of Mg Incorporation on Structural and Optical Properties of Zn2GeO4 : Mn Phosphor

Abstract: The effect of Mg incorporation on structural and optical characteristics of rhombohedral Zn2GeO4 doped with manganese was systematically studied, fixing the concentration of manganese at 2 atom %. The phosphors were prepared by a high-temperature solid-state-reaction technique. The structural properties were studied using X-ray diffraction XRD and optical properties were characterized by diffuse reflectance spectra DRS, photoluminescent excitation PLE, and photoluminescent PL emission spectra. The XRD and DRS analyses reveal that Mg can be successfully alloyed in Zn1.961.96xMg1.96xGeO4:Mn0.04 up to x = 0.30 and forms a solid solution. The PL emission was maximum when 5 atom % Zn was replaced with Mg in comparison to an Mg-free Zn1.96GeO4:Mn0.04 sample. The mechanism of luminescence is identified as resonant transfer from a subbandgap state in the host to Mn 2+ . The PLE and DRS spectra of Zn1.961.96xMg1.96xGeO4:Mn0.04 0 x 0.5 exhibited a blue shift with an increase in Mg concentration. The cell volume was found to be a monotonously increasing function of Mg concentration up to

Studies of nonlinear absorption and aggregation in aqueous solutions of rhodamine 6G using a transient thermal lens technique

Abstract: Dual-beam transient thermal lens studies were carried out in aqueous solutions of rhodamine 6G using 532 nm pulses from a frequency-doubled Nd:YAG laser. The analysis of the observed data showed that the thermal lens method can effectively be utilized to study the nonlinear absorption and aggregation which are taking place in a dye medium.