Department of Physics: Recent submissions
Now showing items 61-80 of 212
-
AC conductivity and dielectric relaxation in CaMg1 / 3 Nb2 / 3 O3
(PERGAMON-ELSEVIER SCIENCE LTD, 2008-05-06)The complex perovskite oxide calcium magnesium niobate, CaMg1/3Nb2/3O3 (CMN) is synthesized by a solid-state reaction technique. Dielectric spectroscopy is applied to investigate the electrical properties of CMN in a ... -
Dielectric relaxation and electronic structure of Ca (Fe1 2 Sb1 2) O3
(AMER PHYSICAL SOC, 2007-10-23)The frequency-dependent dielectric relaxation of calcium-iron-antimonate [Ca (Fe1 2 Sb1 2) O3] (CFS) ceramic, synthesized by a solid-state reaction technique is investigated in the temperature range from 143 to 463 K by ... -
Structural and low frequency dielectric studies of conducting polymer nanocomposites
(NATL INST SCIENCE COMMUNICATIO, 2007-08-01)The intrinsically conducting polymer (ICP), polyaniline (PANI) has been synthesized by chemical polymerization process with the help of water soluble support polymer poly (vinyl pyrrolidone) (PVP). The X-ray diffraction ... -
Dielectric relaxation in perovskite Ba(Zn1/2W1/2)O3
(ELSEVIER SCIENCE SA, 2007-09-25)The complex perovskite oxide barium-zinc-tungstate, Ba(Zn1/2W1/2)O3 (BZW) is synthesized by a solid-state reaction technique. The X-ray diffraction study of the sample at room temperature shows a monoclinic phase. The field ... -
Dielectric relaxation in complex perovskite BaFe1/2Sb1/2O3
(WORLD SCIENTIFIC PUBL CO PTE LTD, 2007-07-10)The complex perovskite oxide barium iron antimonate, BaFe 1/2Sb1/2O3 (BFS) is synthesized by a solid-state reaction technique for the first time. The X-ray diffraction of the sample at room temperature shows a monoclinic ... -
Dielectric relaxation in complex perovskite oxide BaCo1/2W1/2O3
(ELSEVIER SCIENCE BV, 2008-01-01)Polycrystalline BaCo1/2W1/2O3 (BCW) is prepared by the solid-state reaction technique. The X-ray diffraction study of the compound at room temperature reveals the monoclinic phase. The field dependence of the dielectric ... -
Reply to "comment on 'Quantum time-of-flight distribution for cold trapped atomsa'"
(AMER PHYSICAL SOC, 2008-02-22)In their comment Gomes [Phys. Rev. A 77, 026101 (2008)] have questioned the possibility of empirically testable differences existing between the semiclassical time of flight distribution for cold trapped atoms and a quantum ... -
Aspects of nonideal Stern-Gerlach experiment and testable ramifications
(IOP PUBLISHING LTD, 2007-11-16)We critically examine the quantum-mechanical modelling of a measurement process using the Stern-Gerlach (SG) setup in the most general context, probing in particular for nonideal situations, the subtleties involved in the ... -
Entanglement and fidelity signatures of quantum phase transitions in spin liquid models
(AMER PHYSICAL SOC, 2008-03-01)We consider a spin ladder model which is known to have matrix product states as exact ground states with spin liquid characteristics. The model has two critical-point transitions at the parameter values u=0 and. We study ... -
The p53-MDM2 network: From oscillations to apoptosis
(INDIAN ACAD SCIENCES,, 2007-08-01)The p53 protein is well-known for its tumour suppressor function. The p53-MDM2 negative feedback loop constitutes the core module of a network of regulatory interactions activated under cellular stress. In normal cells, ... -
GENE EXPRESSION IS NOISY
(Indian Science News Association, 2007-04-01)Gene expression, leading to protein synthesis, involves biochemical events which are probabilistic in nature. The stochastic effects are prominent when the number of participating molecules is small or the transitions ... -
Quantum critical point and entanglement in a matrix-product ground state
(Elsevier B.V., 2007-04-03)In this paper, we study the entanglement properties of a spin-1 model, the exact ground state of which is given by a matrix product (MP) state. The model exhibits a critical point transition at a parameter value a=0. The ... -
Ion Mobility Studies of Electronically Excited States of Atomic Transition Metal Cations: Development of an Ion Mobility Source for Guided Ion Beam Experiments
(Elsevier B.V, 2007-07-01)The design of an ion mobility source developed to couple to a guided ion beam tandem mass spectrometer is presented. In these exploratory studies, metal ions are created continuously by electron ionization of the volatile ... -
Asymmetry and the shift of the Compton profile
(ELSEVIER SCIENCE BV, 2007-09-21)We show that the conventionally defined asymmetry of the Compton profile (CP) is, to a large extent, simply a shift of CP. Compton scattering is widely used in studying the electron momentum distribution (EMD) of complex ... -
Limitations on the validity of impulse approximation in Compton scattering
(ELSEVIER SCIENCE BV, 2007-08-01)The validity of impulse approximation (IA), which is commonly used in the description of Compton scattering of photons from atomic electrons, is discussed with particular attention to the kinematical region in which the ... -
Spin- 1 2 Heisenberg ladder: Variation of entanglement and fidelity measures close to quantum critical points
(AMER PHYSICAL SOC, 2009-01-05)We consider a two-chain, spin-1/2 antiferromagnetic Heisenberg spin ladder in an external magnetic field H. The spin ladder is known to undergo second-order quantum phase transitions (QPTs) at two critical values H(c1) and ... -
Consistency of nuclear thermometric measurements at moderate excitation
(AMER PHYSICAL SOC, 2008-08-28)A comparison of various thermometric techniques used for the estimation of nuclear temperature has been made from the decay of hot composite (32)S* produced in the reaction (20)Ne (145 MeV) + (12)C. It is shown that the ... -
Fragment emission studies of the 16O+12C reaction
(AMER PHYSICAL SOC, 2008-10-01)The inclusive energy distributions of the fragments (3 <= Z <= 5) emitted in the reaction (16)O+(12)C have been measured in the angular range 9(degrees) to 29(degrees), at the energies 117, 125, 145, and 160 MeV, respectively. ... -
Polyakov-Nambu-Jona-Lasinio model with a Vandermonde term
(Elsevier B.V., 2008-05-29)We extend the Polyakov-Nambu-Jona-Lasinio model for two degenerate flavors by including the effect of the SU(3) measure with a Vandermonde term. This ensures that the Polyakov loop always remains in the domain [0, 1]. The ... -
Functional characteristics of a double positive feedback loop coupled with autorepression
(IOP PUBLISHING LTD, 2008-12-01)We study the functional characteristics of a two-gene motif consisting of a double positive feedback loop and an autoregulatory negative feedback loop. The motif appears in the gene regulatory network controlling the ...