Department of Physics: Recent submissions

Now showing items 101-120 of 212

    • Dielectric relaxation in In(Mg 0.5Ti 0.5)O 3 nanoceramic 

      Agrawal, Lata; Dutta, Alo; Sinha, Tripurari Prasad (Elsevier B.V., 2009)
      The complex perovskite oxide indium magnesium titanate, In(Mg 1/2Ti 1/2)O 3 (IMT) is synthesized by a solid stale reaction technique. Impedance spectroscopy is applied to investigate the electrical properties of IMT in a ...

    • Entanglement in a molecular three-qubit system 

      Pal, Amit Kumar; Bose, Indrani (IOP PUBLISHING LTD, 2010-01-13)
      We study the entanglement properties of a molecular three-qubit system described by the Heisenberg spin Hamiltonian with anisotropic exchange interactions and including an external magnetic field. The system exhibits ...

    • A study of the gamma-ray flux during the total solar eclipse of 1 August 2008 at Novosibirsk, Russia 

      Nayak, Pranaba K.; Gupta, Sunil K.; Jain, Atul; Mazumdar, Indranil; Raha, Sibaji; Saha, Swapan K.; Bobrov, Aleksandr V.; Osipov, Anton; Shwartz, Boris (ELSEVIER SCIENCE BV, 2010-01-01)
      In the past, there have been reports of the observation of decrease in the flux of secondary cosmic gamma-rays during a total solar eclipse. We have measured the flux of secondary cosmic gamma-rays during the total solar ...

    • Determination of the depth of an etch pit through studies of diffraction rings 

      Basu, B.; Dey, S.; Maulik, A.; Raha, Sibaji; Saha, S.; Saha, Swapan K.; Syam, Debapriyo (PERGAMON-ELSEVIER SCIENCE LTD, 2009-04-01)
      A Solid State Nuclear Track Detector (SSNTD) can be used to identify an impinging ion as well as to determine the energy of that ion. The track of the ion is made visible by chemically 'etching' the detector after exposure. ...

    • Optical anisotropy of electronic excitations in elliptical quantum dots 

      Singha, Achintya; Pellegrini, Vittorio; Kalliakos, Sokratis; Karmakar, Biswajit; Pinczuk, Aron; Pfeiffer, Loren N.; West, Ken W. (AMER INST PHYSICS, CIRCULATION & FULFILLMENT DIV, 2009-02-16)
      The authors report that anisotropic confining potentials in laterally coupled semiconductor quantum dots (QDs) have large impacts in optical transitions and energies of intershell collective electronic excitations. The ...

    • Probing collective modes of correlated states of few electrons in semiconductor quantum dots 

      Kalliakos, S.; Rontani, M.; Pellegrini, V.; Pinczuk, A.; Singha, Achintya; Garcia, C. P.; Goldoni, G.; Molinari, E.; Pfeiffer, L. N.; West, K. W. (PERGAMON-ELSEVIER SCIENCE LTD, 2009-09-01)
      Low-lying collective excitations above highly correlated ground states of few interacting electrons confined in GaAs semiconductor quantum dots are probed by resonant inelastic light scattering. We highlight that separate ...

    • Engineering artificial graphene in a two-dimensional electron gas 

      Gibertini, M.; Singha, Achintya; Pellegrini, Vittorio; Polini, Marco; Vignale, Giovanni; Pinczuk, Aron; Pfeiffer, Loren N.; West, Ken W. (AMER PHYSICAL SOC, 2009-06-01)
      At low energy, electrons in doped graphene sheets behave like massless Dirac fermions with a Fermi velocity, which does not depend on carrier density. Here we show that modulating a two-dimensional electron gas with a ...

    • Compton scattering revisited 

      Pratt, R. H.; LaJohn, L. A.; Florescu, V.; Suric, T.; Chatterjee, Barun Kumar; Roy, S. C. (PERGAMON-ELSEVIER SCIENCE LTD, 2010-02-01)
      We review the standard theory of Compton scattering from bound electrons, and we describe recent findings that require modification of the usual understanding. noting the nature of consequences for experiment. The subject ...

    • Light-charged-particle emission from hot S-32* formed in Ne-20+C-12 reaction 

      Dey, A.; Bhattacharya, Sabita; Bhattacharya, C.; Banerjee, K.; Rana, T. K.; Kundu, S.; Banerjee, S. R.; Mukhopadhyay, S.; Gupta, Dhruba; Saha, R. (SPRINGER, 2009-07-01)
      Inclusive energy distributions for light charged particles (p, d, t and alpha) have been measured in the Ne-20 (158, 170, 180, 200MeV)+ C-12 reactions in the angular range 10 degrees-50 degrees. Exclusive light-charged-particle ...

    • Variation of neutron detection characteristics with dimension of BC501A neutron detector 

      Banerjee, K.; Ghosh, T. K.; Kundu, S.; Rana, T. K.; Bhattacharya, C.; Meenaa, J. K.; Mukherjee, G.; Mali, P.; Gupta, Dhruba; Mukhopadhyay, S.; Pandit, D.; Banerjee, S. R.; Bhattacharya, Sabita; Bandyopadhyay, T.; Chatterjee, S. (ELSEVIER SCIENCE BV, 2009-09-21)
      A systematic study of the variation of neutron detection characteristics (efficiency, pulse shape discrimination) and the intrinsic time resolution with the active volume of the detector has been carried out with liquid ...

    • A new method for measurement of droplet size distribution in superheated emulsions 

      Mondal, P. K.; Sarkar, R.; Chatterjee, Barun Kumar (IOP PUBLISHING LTD, 2010-04-01)
      Superheated emulsion contains micron-sized superheated liquid droplets suspended in a host liquid medium. The superheated droplets nucleate to vapor bubbles when energetic radiation deposits a sufficient amount of energy ...

    • Measurement of droplet size distribution in superheated emulsion 

      Mondal, P.K.; Sarkar, R.; Datta, M.; Chatterjee, Barun Kumar; Roy, B.; Roy, S.C. (Elsevier B.V, 2009)
      Superheated liquids nucleate to vapour as a result of radiation induced phase transition. Superheated emulsion detectors have been developed using this property of superheated liquid. The emulsion is prepared by shearing ...

    • Two-state modeling of the superheated emulsion detector 

      Mondal, P. K.; Chatterjee, Barun Kumar (ELSEVIER SCIENCE BV, 2009-06-11)
      he non-monotonic nature of the decay of superheated emulsions, observed when it is periodically exposed to ionising radiations, indicates presence of multiple decaying species in the emulsion. A simple two-state model of ...

    • Threshold collision-induced dissociation of Sr2+(H2O)(x) complexes (x=1-6): An experimental and theoretical investigation of the complete inner shell hydration energies of Sr2+ 

      Carl, D. R.; Chatterjee, Barun Kumar; Armentrout, P. B. (AMER INST PHYSICS, 2010-01-28)
      The sequential bond energies of Sr2+(H2O)(x) complexes, where x=1-6, are determined by threshold collision-induced dissociation using a guided ion beam tandem mass spectrometer equipped with an electrospray ionization ...

    • Entanglement cost of nonlocal measurements 

      Bandyopadhyay, Somshubhro; Brassard, G.; Kimmel, S.; Wootters, W. K. (AMER PHYSICAL SOC, 2009-07-01)
      For certain joint measurements on a pair of spatially separated particles, we ask how much entanglement is needed to carry out the measurement exactly. For a class of orthogonal measurements on two qubits with partially ...

    • Entanglement and perfect discrimination of a class of multiqubit states by local operations and classical communication 

      Bandyopadhyay, Somshubhro (AMER PHYSICAL SOC, 2010-02-01)
      It is shown that while entanglement ensures difficulty in discriminating a set of mutually orthogonal states perfectly by local operations and classical communication (LOCC), entanglement content does not. In particular, ...

    • Contextuality within quantum mechanics manifested in subensemble mean values 

      Pan, A. K.; Home, Dipankar (ELSEVIER SCIENCE BV, 2009-09-14)
      For spin-1/2 particles, using a suitable Mach-Zehnder-type setup with a spin-flipper, we argue that it is a direct consequence of the quantum mechanical treatment that an experimentally verifiable subensemble mean of the ...

    • Reply to "Comment on 'Contextuality within quantum mechanics manifested in subensemble mean values' [Phys. Lett. A 373 (2009) 3430]" [Phys. Lett. A 374 (2010) 1397] 

      Pan, A. K.; Home, Dipankar (ELSEVIER SCIENCE BV, 2010-04-26)
      In this reply, we point out that the claim by De Zela (2010) [2] is unjustified because the setup he discusses is not equivalent to the setup analysed in our paper (Pan and Home (2009) [1]). Hence his subsequent argument ...

    • Information transfer using a single particle path-spin hybrid entangled state 

      Pramanik, T.; Adhikari, S.; Majumdar, A. S.; Home, Dipankar; Pan, A. K. (ELSEVIER SCIENCE BV, 2010-02-15)
      he path-spin entangled state of a single spin-1/2 particle is considered which is generated by using a beam-spitter and a spin-flipper. Using this hybrid entanglement at the level of a single particle as a resource, we ...

    • Dark energy from quantum wave function collapse of dark matter 

      Majumdar, A. S.; Home, Dipankar; Sinha, Siddhartha (ELSEVIER SCIENCE BV, 2009-08-24)
      Dynamical wave function collapse models entail the continuous liberation of a specified rate of energy arising from the interaction of a fluctuating scalar field with the matter wave function. We consider the wave function ...