Searching Arxiv, refresh for possibly better results.

Results for "Pramoda K. Nayak"

total 84202took 0.19s
Resonantly hybridised excitons in moiré superlattices in van der Waals heterostructuresApr 12 2019Atomically-thin layers of two-dimensional materials can be assembled in vertical stacks held together by relatively weak van der Waals forces, allowing for coupling between monolayer crystals with incommensurate lattices and arbitrary mutual rotation. ... More
Proton-proton physics in ALICEJan 26 2007The ALICE experiment has several unique features which makes it an important contributor to proton-proton physics at the LHC, in addition to its specific design goal of studying the physics of strongly interacting matter in heavy-ion collisions. The unique ... More
Event-by-event fluctuations and the QGP phase transitionAug 14 2006Fluctuations of thermodynamic quantities are fundamental to the study of QGP phase transition. Event-by-event fluctuations of many quantities have been studied by dedicated heavy-ion experiments. A brief review of recent experimental results is presented. ... More
Hard To Soft Magnetic Transition of Co in Co/Au Multilayer FilmsAug 19 2016Oct 19 2016We report hard to soft magnetic transition of Co in Co/Au multilayer films prepared by e-beam evaporation. The coercive field of the films reduced systematically with increasing number of bilayers, as observed by MOKE. This was due to increase in amorphization ... More
Hard To Soft Magnetic Transition of Co in Co/Au Multilayer FilmsAug 19 2016Aug 31 2016We report hard to soft magnetic transition of Co in Co/Au multilayer films prepared by e-beam evaporation. The coercive field of the films reduced systematically with increasing number of bilayers, as observed by MOKE. This was due to increase in amorphization ... More
Observation of Topological Hall Effect and Signature of Room Temperature Antiskyrmions in Mn-Ni-Ga D2d Heusler magnetsApr 03 2019Topologically stable nontrivial spin structures, such as skyrmions and antiskyrmions, display a large topological Hall effect owing to their quantized topological charge. Here, we present the finding of a large topological Hall effect beyond room temperature ... More
Field induced topological Hall effect in non-coplanar triangular antiferromagnetic geometry of Mn3SnMar 26 2019Non-collinear triangular antiferromagnets with a coplanar spin arrangement and vanishing net magnetic moment can exhibit a large anomalous Hall effect owing to their non-vanishing momentum space Berry curvature. Here we show the existence of a large field ... More
The Hadamard Determinant Inequality - Extensions to Operators on a Hilbert SpaceApr 18 2017Oct 16 2017A generalization of classical determinant inequalities like Hadamard's inequality and Fischer's inequality is studied. For a version of the inequalities originally proved by Arveson for positive operators in von Neumann algebras with a tracial state, ... More
On a New Ring Invariant - Towards a Framework for Rank IdentitiesJan 24 2018For a square matrix $A$ over a field $F$, it is known that $\mathrm{rank}(A) + \mathrm{rank}(I-A) = \mathrm{rank}(I) + \mathrm{rank}(A-A^2)$. The main goal of this article is to start a program to characterize and generalize such rank identities by constructing ... More
The Quadratic Spin Squeezing OperatorsNov 07 2007Feb 29 2008We discuss generic spin squeezing operators (quadratic in angular momentum operators) capable of squeezing out quantum mechanical noise from a system of two-level atoms (spins) in a coherent state. Such systems have been considered by Kitagawa and Ueda ... More
Jensen's inequality in finite subdiagonal algebrasJul 31 2018Sep 07 2018Let $\mathscr{M}$ be a finite von Neumann algebra with a faithful normal tracial state $\tau$ and $\mathfrak{A}$ be a finite subdiagonal subalgebra of $\mathscr{M}$ with respect to a $\tau$-preserving faithful normal conditional expectation $\Phi$ on ... More
An operator inequality for range projectionsApr 25 2018Jun 18 2018By a result of Lundquist-Barrett, it follows that the rank of a positive semi-definite matrix is less than or equal to the sum of the ranks of its principal diagonal submatrices when written in block form. In this article, we take a general operator algebraic ... More
Pasting pseudofunctorsJun 24 2004We give an abstract criterion for pasting pseudofunctors on two subcategories of a category into a pseudofunctor on the whole category. As an application we extend the variance theory of the twisted inverse image $(-)^!$ over schemes to that over formal ... More
Search for DCC in relativistic heavy-ion collisions : Possibilities and LimitationsNov 07 2002Mar 18 2003The experimental observation of disoriented chiral condensate is affected due to various physical and detector related effects. We study and quantify the strength of the experimental signal, ``neutral pion fraction'' within the framework of a simple DCC ... More
Imaging of interlayer coupling in van der Waals heterostructures using a bright-field optical microscopeDec 23 2016May 01 2017Vertically stacked atomic layers from different layered crystals can be held together by van der Waals forces, which can be used for building novel heterostructures, offering a platform for developing a new generation of atomically thin, transparent and ... More
Inverting a permutation is as hard as unordered searchJul 17 2010Mar 11 2011We show how an algorithm for the problem of inverting a permutation may be used to design one for the problem of unordered search (with a unique solution). Since there is a straightforward reduction in the reverse direction, the problems are essentially ... More
The effect of hydrostatic pressure and uniaxial strain on the electronic structure of Pb$_{\text{1-x}}$Sn$_{\text{x}}$TeAug 17 2015The electronic structure of Pb$_{1-x}$Sn$_{x}$Te is studied by using the relativistic Korringa-Kohn-Rostoker Green function method in the framework of density functional theory. For all concentrations $x$, Pb$_{1-x}$Sn$_{x}$Te is a direct semiconductor ... More
Short proofs of the Quantum Substate TheoremMar 31 2011Jan 12 2012The Quantum Substate Theorem due to Jain, Radhakrishnan, and Sen (2002) gives us a powerful operational interpretation of relative entropy, in fact, of the observational divergence of two quantum states, a quantity that is related to their relative entropy. ... More
The space complexity of recognizing well-parenthesized expressions in the streaming model: the Index function revisitedApr 19 2010Jul 10 2014We show an Omega(sqrt{n}/T) lower bound for the space required by any unidirectional constant-error randomized T-pass streaming algorithm that recognizes whether an expression over two types of parenthesis is well-parenthesized. This proves a conjecture ... More
The Effect of Ionic Composition on Acoustic Phonon Speeds in Hybrid Perovskites from Brillouin Spectroscopy and Density Functional TheoryJan 10 2018Hybrid organic-inorganic perovskites (HOIPs) have recently emerged as highly promising solution-processable materials for photovoltaic (PV) and other optoelectronic devices. HOIPs represent a broad family of materials with properties highly tuneable by ... More
Isoscalar Giant Resonance Strengths in $^{32}$S and possible excitations of superdeformed and $^{28}$Si + $α$ cluster bandheadsOct 01 2013Isoscalar giant resonances and low spin states in $^{32}$S have been measured with inelastic $\alpha$ scattering at extremely forward angles including zero degrees at E$_{\alpha}$ = 386 MeV. By applying the multipole decomposition analysis, various excited ... More
Effect of Foregrounds on the CMBR Multipole AlignmentJul 12 2010We analyze the effect of foregrounds on the observed alignment of CMBR quadrupole and octopole. The alignment between these multipoles is studied by using a symmetry based approach which assigns a principal eigenvector (PEV) or an axis with each multipole. ... More
Testing statistical Isotropy in Cosmic Microwave Background Polarization mapsJul 13 2017Jan 03 2018We apply our symmetry based Power tensor technique to test conformity of PLANCK Polarization maps with statistical isotropy. On a wide range of angular scales (l=40-150), our preliminary analysis detects many statistically anisotropic multipoles in foreground ... More
Chern-Simons-Higgs transitions out of Topological Superconducting PhasesJul 01 2015In this study, we examine effective field theories of superconducting phases with topological order, making connection to proposed realizations of exotic topological phases(including those hosting Ising and Fibonacci anyons) in superconductor-quantum ... More
Iris Biometric System using a hybrid approachOct 27 2014Iris Recognition Systems are ocular- based biometric devices used primarily for security reasons. The complexity and the randomness of the Iris, amongst various other factors, ensure that this biometric system is inarguably an exact and reliable method ... More
Multiplicity Distributions and Charged-neutral FluctuationsMar 21 2001Results from the multiplicity distributions of inclusive photons and charged particles, scaling of particle multiplicities, event-by-event multiplicity fluctuations, and charged-neutral fluctuations in 158$\cdot A$ GeV Pb+Pb collisions are presented and ... More
Heavy Ions: Results from the Large Hadron ColliderJan 20 2012On November 8, 2010 the Large Hadron Collider (LHC) at CERN collided first stable beams of heavy ions (Pb on Pb) at center-of-mass energy of 2.76 TeV/nucleon. The LHC worked exceedingly well during its one month of operation with heavy ions, delivering ... More
Quark-Gluon Plasma: Present and FutureApr 08 2008We review a sample of the experimental results from AGS to SPS and RHIC and their interpretations towards understanding of the Quark-Gluon Plasma. We discuss extrapolations of these results to the upcoming LHC experiments. Finally, we present the plans ... More
Overview of event-by-event analysis of high energy nuclear collisionsJun 19 2007The event-by-event analysis of high energy nuclear collisions aims at revealing the richness of the underlying event structures and provide unique measures of dynamical fluctuations associated with QGP phase transition. The major challenge in these studies ... More
Photonic crystal formation on optical nanofibers using femtosecond laser ablation techniqueOct 29 2012We demonstrate that thousands of periodic nano-craters are fabricated on a subwavelength-diameter tapered optical fiber, an optical nanofiber, by irradiating with just a single femtosecond laser pulse. A key aspect of the fabrication is that the nanofiber ... More
A Preshower Photon Multiplicity Detector for the WA98 ExperimentJul 28 1998A high granularity preshower detector has been fabricated and installed in the WA98 Experiment at the CERN SPS for measuring the spatial distribution of photons produced in the forward region in lead ion induced interactions. Photons are counted by detecting ... More
Searches for beyond Standard Model Higgs bosons at CMSOct 28 2013A search for neutral Higgs bosons in the minimal supersymmetric extension of the Standard Model (MSSM) decaying to a pair of b quarks or a pair of tau leptons, using events recorded by the CMS experiment at the LHC in 2011 and 2012 at the centre-of-mass ... More
Interacting boson problems are QMA-hardMay 20 2009Computing the ground-state energy of interacting electron (fermion) problems has recently been shown to be hard for QMA, a quantum analogue of the complexity class NP. Fermionic problems are usually hard, a phenomenon widely attributed to the so-called ... More
Multiplicity Distributions and Charged-Neutral FluctuationsAug 29 2001We discuss the importance of event-by-event fluctuations in relativistic heavy-ion collisions. We present results of multiplicity fluctuations of photons and charged particles produced in 158$\cdot A$ GeV Pb+Pb collisions at CERN-SPS. Multiplicity fluctuations ... More
Search for DCC in 158A GeV Pb+Pb CollisionsSep 30 1999A detailed analysis of the phase space distributions of charged particles and photons have been carried out using two independent methods. The results indicate the presence of nonstatistical fluctuations in localized regions of phase space.
Soft Phonon Mode Dynamics in Aurivillius Type StructuresSep 03 2016Jun 12 2017We report the dynamics of soft phonon modes and their role towards the various structural transformations in Aurivillius materials by employing terahertz frequency-domain spectroscopy, atomic pair distribution function analysis, and first-principles calculations. ... More
Direct proton decay of the isoscalar giant dipole resonance in 208PbMar 30 2009The excitation and subsequent proton decay of the isoscalar giant dipole resonance (ISGDR) in $^{208}$Pb have been investigated via the $^{208}$Pb($\alpha, \alpha^{\prime}p)^{207}$Tl reaction at 400 MeV. Excitation of the ISGDR has been identified by ... More
Electron Electric Dipole Moment and Hyperfine Interaction Constants for ThOJan 10 2014Mar 28 2014A recently implemented relativistic four-component configuration interaction approach to study ${\cal{P}}$- and ${\cal{T}}$-odd interaction constants in atoms and molecules is employed to determine the electron electric dipole moment effective electric ... More
Wind speed prediction using different computing techniquesFeb 15 2014Wind is slated to become one of the most sought after source of energy in future. Both onshore as well as offshore wind farms are getting deployed rapidly over the world. This paper evaluates a neural network based time series approach to predict wind ... More
Fuzzy and interval finite element method for heat conduction problemSep 26 2012Traditional finite element method is a well-established method to solve various problems of science and engineering. Different authors have used various methods to solve governing differential equation of heat conduction problem. In this study, heat conduction ... More
Reconstruction of physics objects in the CMS detectorOct 28 2013The reconstruction and identification of physics objects in the CMS detector, in the context of the charged Higgs boson search analysis, are presented. The reconstruction algorithms and their performance in 7 TeV and 8 TeV LHC data are discussed. The ... More
Effect of Rope Hadronisation on Strangeness Enhancement in p$-$p collisions at LHC energiesDec 19 2018The p$-$p collisions at high multiplicity at LHC show small scale collective effects similar to that observed in heavy ion collisions such as enhanced production of strange and multi-strange hadrons, long range azimuthal correlations, etc. The observation ... More
Energy dependence study of directed flow in Au+Au collisions using an improved coalescence in AMPT modelApr 08 2019The rapidity-odd component of directed flow ($v_{1}$) of identified hardons ($\pi^{\pm}$, $K^{\pm}$, $K^{0}_{S}$, p, $\bar{\rm p}$, $\phi$, $\Xi^{\pm}$, $\Lambda$, $\bar{\Lambda}$) and partons (u, $\bar{\rm u}$, d, $\bar{\rm d}$, s, $\bar{\rm s}$) in ... More
Eigenstate Thermalisation in the conformal Sachdev-Ye-Kitaev model: an analytic approachMar 01 2019The Sachdev-Ye-Kitaev (SYK) model provides an uncommon example of a chaotic theory that can be analysed analytically. In the deep infrared limit, the original model has an emergent conformal (reparametrisation) symmetry that is broken both spontaneously ... More
Quasiparticle bandgap engineering of graphene and graphone on hexagonal boron nitride substrateOct 26 2011Graphene holds great promise for post-silicon electronics, however, it faces two main challenges: opening up a bandgap and finding a suitable substrate material. In principle, graphene on hexagonal boron nitride (hBN) substrate provides potential system ... More
Proton decay from the isoscalar giant dipole resonance in $^{58}$NiJun 23 2009Oct 08 2009Proton decay from the 3$\hbar\omega$ isoscalar giant dipole resonance (ISGDR) in $^{58}$Ni has been measured using the ($\alpha,\alpha'p$) reaction at a bombarding energy of 386 MeV to investigate its decay properties. We have extracted the ISGDR strength ... More
Single Atoms on an Optical NanofiberSep 18 2007We show that single-atoms can be trapped on the surface of a subwavelength-diameter silica-fiber, an optical nanofiber, without any external field, and that single photons spontaneously emitted from the atoms can be readily detected through the single ... More
The Giant Monopole Resonance in the $^{112-124}$Sn Isotopes and the Symmetry Energy Term in Nuclear IncompressibilitySep 20 2007We have investigated the isoscalar giant monopole resonance (GMR) in the Sn isotopes, using inelastic scattering of 400-MeV $\alpha$-particles at extremely forward angles, including 0 deg. A value of -550 \pm 100 MeV has been obtained for the asymmetry ... More
Electromagnetic signals from Au+Au collisions at RHIC energy, $\sqrt{s_{NN}}$=200 GeV and Pb+Pb collisions at LHC energy, $\sqrt{s_{NN}}$=2.76 TeVOct 15 2012We analyse the recently available experimental data on direct photon productions from Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV RHIC and from Pb+Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV LHC energies. The transverse momentum ($p_T$) distributions have ... More
Fabrication of a centimeter-long cavity on a nanofiber for cavity QEDJan 24 2017We report the fabrication of a 1.2 cm long cavity directly on a nanofiber using femtosecond laser ablation. The cavity modes with finesse value in the range 200-400 can still maintain the transmission between 40-60%, which can enable "strong-coupling" ... More
Wave Propagation in 1-D Spiral geometryOct 18 2014In this article, we investigate the wave equation in spiral geometry and study the modes of vibrations of a one-dimensional (1-D) string in spiral shape. Here we show that the problem of wave propagation along a spiral can be reduced to Bessel differential ... More
Fluorescence photon measurements from single quantum dots on an optical nanofiberDec 03 2011We experimentally investigate the fluorescence photon emission characteristics for single q-dots by using optical nanofibers. We demonstrate that single q-dots can be deposited along an optical nanofiber systematically and reproducibly with a precision ... More
A Chern-Simons Effective Field Theory for the Pfaffian Quantum Hall StateNov 11 1997We present a low-energy effective field theory describing the universality class of the Pfaffian quantum Hall state. To arrive at this theory, we observe that the edge theory of the Pfaffian state of bosons at $\nu=1$ is an $SU(2)_2$ Kac-Moody algebra. ... More
Protein translocation without specific quality control in a computational model of the Tat systemAug 20 2014The twin-arginine translocation (Tat) system transports folded proteins of various sizes across both bacterial and plant thylakoid membranes. The membrane-associated TatA protein is an essential component of the Tat translocon, and a broad distribution ... More
Topological exciton Fermi surfaces in two-component fractional quantized Hall insulatorsNov 03 2016Mar 21 2018A wide variety of two-dimensional electron systems (2DES) allow for independent control of the total and relative charge density of two-component fractional quantum Hall (FQH) states. In particular, a recent experiment on bilayer graphene (BLG) observed ... More
Fundamental String (Membrane) Orbiting D5(M5)-branesNov 04 2010We study fundamental string (F-string) dynamics near D5-brane in some limits. We find that when the angular momentum of the probe is proportional to string length (l_s) and square root of string coupling constant {g_s}, the F-string lies in its metastable ... More
Study of the Fluctuations of Net-charge and Net-protons Using Higher Order MomentsJul 27 2009Sep 11 2009We present the STAR preliminary results on mid-rapidity and low transverse momentum mean, standard deviation, skewness, and kurtosis of net-charge and net-proton distributions in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}$ = 200 GeV for various collision ... More
Small-x Physics with the ALICE experiment at the CERN-LHCSep 12 2010High energy p-p, p-Pb and Pb-Pb collisions at the CERN-LHC offer unprecedented opportunities for studying wide variety of physics at small Bjorken-x. Here we discuss capabilities of the ALICE experiment at the CERN-LHC for probing small-x QCD physics. ... More
Two introductory lectures on high energy QCD and heavy ion collisionsOct 20 2008These introductory lectures present a broad overview of the physics of high parton densities in QCD and its application to our understanding of the early time dynamics in heavy ion collisions.
Measuring radial flow of partonic and hadronic phases in relativistic heavy ion collisionJul 17 2009Dec 14 2009It has been shown that the thermal photon and the lepton pair spectra can be used to estimate the radial velocity of different phases of the matter formed in nuclear collisions at ultra-relativistic energies. We observe a non-monotonic variation of the ... More
Toward low-latency coincident precessing and coherent aligned-spin gravitational-wave searches of compact binary coalescences with particle swarm optimizationNov 06 2018Nov 15 2018We investigate the use of particle swarm optimization (PSO) algorithm for detection of gravitational-wave signals from compact binary coalescences. We show that the PSO is fast and effective in searching for gravitational wave signals. The PSO-based aligned-spin ... More
Interplay Between Structural Randomness, Composite Disorder, and Electrical Response: Resonances and Transient Delays in Complex Impedance NetworksMar 02 2009We study the interplay between structural and conductivity (composite) disorder and the collective electrical response in random networks models. Translating the problem of time-dependent electrical response (resonance and transient relaxation) in binary ... More
Tomographic approach to resolving the distribution of LISA Galactic binariesDec 02 2005The space based gravitational wave detector LISA is expected to observe a large population of Galactic white dwarf binaries whose collective signal is likely to dominate instrumental noise at observational frequencies in the range 10^{-4} to 10^{-3} Hz. ... More
Bottom and Charm Production at LHC and RHICSep 21 2000Nov 11 2000We study $b\bar{b}$ and $c\bar{c}$ production and the influence of nuclear shadowing at LHC and RHIC energies. We find a significant reduction in the production cross section of both charm and bottom at RHIC and LHC. Bound states such as $\Upsilon$ and ... More
Sterile Neutrino Assisted Dominant Seesaw Mechanisms, Double Beta Decay, Leptogenesis, and Other PredictionsJul 25 2016Jul 28 2016In a recent review Mohapatra has discussed how type-I seesaw mechanism suppressed by fine tuning of Yukawa couplings, or specific textures of associated fermion mass matrices, can form the basis of neutrino masses in TeV scale $W_R$ boson models. In this ... More
Weak electron-phonon coupling in the early alkali atomic wiresAug 13 2014The structural, electronic and vibrational properties of atomic wires composed of the early alkali metals lithium and sodium are studied using density functional perturbation theory. The s-like electronic states near the Fermi level couple very weakly ... More
New mechanism for Type-II seesaw dominance in SO(10) with low-mass Z-prime, RH neutrinos, and verifiable LFV, LNV, and proton decayDec 11 2013Oct 01 2015Dominance of type-II seesaw mechanism for neutrino masses has attracted considerable attention because of a number of advantages. We show a novel approach to achieve Type-II seesaw dominance in non-supersymmetric $SO(10)$ grand unification where a low ... More
Observation of enhanced exchange bias behavior in NiCoMnSb Heusler alloysJun 01 2010We report the observation of large exchange bias in Ni50-xCoxMn38Sb12 Heusler alloys with x=0, 2, 3, 4, 5, which is attributed to the coexistence of ferromagnetic and antiferromagnetic phases in the martensitic phase. The phase coexistence is possibly ... More
Giant inverse magnetocaloric effect near room temperature in Co substituted NiMnSb Heusler alloysJun 01 2010The effect of Co on the structural, magnetic and magnetocaloric effect (MCE) of Ni50-xCoxMn38Sb12 (x=0,2,3,4,5) Heusler alloys was studied. Using x-ray diffraction, we show the evolution of the martensitic phase from the austenite phase. The martensitic ... More
Irreversibility of field-induced magnetostructural transition in NiCoMnSb shape memory alloy revealed by magnetization, transport and heat capacity studiesJun 01 2010The effects of magnetic field on the martensitic transition have been studied in Ni45Co5Mn38Sb12. We find a large field-induced irreversibility in this system, as revealed by the field dependence of resistivity, magnetization, and heat capacity data. ... More
Dilepton events with displaced vertices, double beta decay, and resonant leptogenesis with Type-II seesaw dominance, TeV scale $Z'$ and heavy neutrinosSep 21 2015Sep 29 2015In a class of Type-II seesaw dominated $SO(10)$ models proposed recently with heavy neutrinos, extra $Z'$ boson, and resonant leptogenesis, at first we show that the lightest first generation sterile neutrino that mediates dominant contributions to neutrinoless ... More
Note on I-brane Near Horizon PP-wave BackgroundDec 13 2010We find out a PP-wave spacetime with constant Neveu-Schwarz (NS) three form flux by taking a Penrose limit on the 1+1 dimensional intersection of two orthogonal stacks of fivebranes in type IIB string theory. We further find out an intersecting (D1-D5)-brane ... More
TaN, a molecular system for probing ${\cal{P,T}}$-violating hadron physicsNov 01 2015All-electron configuration interaction theory in the framework of the Dirac-Coulomb Hamiltonian has been applied to the TaN molecule, a promising candidate in the search for Beyond-Standard-Model physics in both the hadron and the lepton sector of matter. ... More
Gyroscopic Precession and Inertial Forces in Axially Symmetric Stationary SpacetimesAug 12 1998We study the phenomenon of gyroscopic precession and the analogues of inertial forces within the framework of general relativity. Covariant connections between the two are established for circular orbits in stationary spacetimes with axial symmetry. Specializing ... More
Beam energy dependence of pseudorapidity distributions of charged particles produced in heavy-ion collisions at RHIC and LHC energiesApr 29 2016Heavy-ion collisions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the Large Hadron Collider at CERN probe matter at extreme conditions of temperature and energy density. Most of the global properties of the collisions can ... More
Characterization of relativistic heavy-ion collisions at the Large Hadron Collider through temperature fluctuationsApr 17 2015We propose to characterize heavy-ion collisions at ultra-relativistic energies by using fluctuations of energy density and temperature. Temperature fluctuations on an event-by-event basis have been studied both in terms of global temperature of the event, ... More
Nanofibers with Bragg gratings from equidistant holesMar 09 2011We study nanofibers with Bragg gratings from equidistant holes. We calculate analytically and numerically the reflection and transmission coefficients for a single grating and also for a cavity formed by two gratings. We show that the reflection and transmission ... More
Photonic crystal nanofiber using an external gratingJun 02 2013We implement a photonic crystal nanofiber device by reversibly combining an optical nanofiber and a nanofabricated grating. Using the finite-difference time-domain method, we design the system for minimal optical loss while tailoring the resonant wavelength ... More
Maps of the Little Bangs Through Energy Density and Temperature FluctuationsMay 15 2014In this letter we propose for the first time to map the heavy-ion collisions at ultra-relativistic energies, similar to the maps of the cosmic microwave background radiation, using fluctuations of energy density and temperature in small phase space bins. ... More
Ab-initio Study of Size and Strain Effects on the Electronic Properties of Si NanowiresOct 07 2010We have applied density-functional theory (DFT) based calculations to investigate the size and strain effects on the electronic properties, such as band structures, energy gaps, and effective masses of the electron and the hole, in Si nanowires along ... More
Present Status and Future of DCC AnalysisFeb 22 1998Disoriented Chiral Condensates (DCC) have been predicted to form in high energy heavy ion collisions where the approximate chiral symmetry of QCD has been restored. This leads to large imbalances in the production of charged to neutral pions. Sophisticated ... More
Diagonal and off-diagonal susceptibilities of conserved quantities in relativistic heavy-ion collisionsJun 30 2016Oct 26 2016Susceptibilities of conserved quantities, such as baryon number, strangeness and electric charge are sensitive to the onset of quantum chromodynamics (QCD) phase transition and are expected to provide information on the matter produced in heavy-ion collision ... More
Time Delay Interferometry for LISA with one arm dysfunctionalJan 27 2010In order to attain the requisite sensitivity for LISA - a joint space mission of the ESA and NASA- the laser frequency noise must be suppressed below the secondary noises such as the optical path noise, acceleration noise etc. By combining six appropriately ... More
Optimising LISA orbits: The projectile solutionSep 11 2008LISA is a joint space mission of the NASA and the ESA for detecting low frequency gravitational waves (GW) in the band $10^{-5} - 0.1$ Hz. The proposed mission will use coherent laser beams which will be exchanged between three identical spacecraft forming ... More
Affine Kac-Moody symmetric spaces associated with untwisted Kac-Moody algebrasDec 13 2013In this paper we have computed all the affine Kac-Moody symmetric spaces which are tame Frechet manifolds starting from the Vogan diagrams related to the affine untwisted Kac-Moody algebras. The detail computation of affine Kac-Moody symmetric spaces ... More
A Fluctuation Probe of Disoriented Chiral CondensatesJan 17 2002Jan 25 2002We show that an event-by-event fluctuation of the ratio of neutral pions or resulting photons to charged pions can be used as an effective probe for the formation of disoriented chiral condensates. The fact that the neutral pion fraction produced in case ... More
Effect of VSR invariant Chern-Simon Lagrangian on photon polarizationApr 20 2015We propose a generalization of the Chern-Simon (CS) Lagrangian which is invariant under the SIM(2) transformations but not under the full Lorentz group. We study the effect of such a term on radiation propagating over cosmological distances. We find that ... More
Kinetic arrest related to a first-order ferrimagnetic to antiferromagnetic transition in the Heusler compound Mn2PtGaApr 16 2013We report a magnetization study of the Heusler compound Mn2PtGa that shows the existence of a magnetic-glass state. Mn2PtGa shows a first-order ferromagnetic (FM)/ferrimagnetic (FI) to antiferromagnetic (AFM) transition in contrast to the martensitic ... More
Fluctuations in Charged Particle Multiplicities in Relativistic Heavy-Ion CollisionsMar 07 2016Jun 17 2016Multiplicity distributions of charged particles and their event-by-event fluctuations have been compiled for relativistic heavy-ion collisions from the available experimental data at Brookhaven National Laboratory and CERN and also by the use of an event ... More
General relativistic treatment of LISA optical linksMay 28 2008LISA is a joint space mission of the NASA and the ESA for detecting low frequency gravitational waves in the band $10^{-5} - 1$ Hz. In order to attain the requisite sensitivity for LISA, the laser frequency noise must be suppressed below the other secondary ... More
Black Holes in Non-flat Backgrounds: the Schwarzschild Black Hole in the Einstein UniverseJun 12 2000Oct 24 2000As an example of a black hole in a non-flat background a composite static spacetime is constructed. It comprises a vacuum Schwarzschild spacetime for the interior of the black hole across whose horizon it is matched on to the spacetime of Vaidya representing ... More
First-principles investigation of spin polarized conductance in atomic carbon wireAug 20 2004We analyze spin-dependent energetics and conductance for one dimensional (1D) atomic carbon wires consisting of terminal magnetic (Co) and interior nonmagnetic (C) atoms sandwiched between gold electrodes, obtained employing first-principles gradient ... More
Energy levels of an anharmonic oscillator in both weak and strong coupling limit using convergency of Morse-Feshbach non-linear perturbation seriesSep 11 2013We make an extensive rigorous study on convergent behaviour of Morse-Feshbach nonlinear perturbation series (MFNPS) to find out energy levels of the anharmonic oscillator (AHO) in both weak and strong coupling limit. We develop a new method of multi step ... More
Fractional Chern insulator edges and layer-resolved lattice contactsOct 04 2018Nov 12 2018Fractional Chern insulators (FCIs) realized in fractional quantum Hall systems subject to a periodic potential are topological phases of matter for which space group symmetries play an important role. In particular, lattice dislocations in an FCI can ... More
UHop: An Unrestricted-Hop Relation Extraction Framework for Knowledge-Based Question AnsweringApr 02 2019In relation extraction for knowledge-based question answering, searching from one entity to another entity via a single relation is called "one hop". In related work, an exhaustive search from all one-hop relations, two-hop relations, and so on to the ... More
Measuring initial temperature through photon to dilepton ratio in heavy ion collisionJun 03 2008Jul 02 2008Theoretical calculation of transverse momentum($p_T$) distribution of thermal photons and dileptons originating from ultra-relativistic heavy ion collisions suffer from several uncertainties since the evaluation of these spectra needs various inputs which ... More
Thermal photons to dileptons ratio at LHCMay 24 2007It is shown that the ratio of transverse momentum (p_T) distribution of thermal photons to dileptons produced in heavy ion collisions reaches a plateau above p_T=1 GeV. We argue that the value of the ratio in the plateau region can be used to estimate ... More
The horn in the kaon to pion ratioJun 15 2010Aug 31 2010A microscopic approach has been employed to study the kaon productions in heavy ion collisions. The momentum integrated Boltzmann equation has been used to study the evolution of strangeness in the system formed in heavy ion collision at relativistic ... More
Signals of Statistical Anisotropy in WMAP Foreground-Cleaned MapsNov 11 2008Nov 28 2008Recently a symmetry-based method to test for statistical isotropy of the cosmic microwave background was developed. We apply the method to template-cleaned 3-year and 5-year WMAP-$DA$ maps. We examine a wide range of angular multipoles from $2 < l < 300$. ... More