**ap**

**An International Research Journal**

**AJP**

**SSN : 0971 - 3093**

**Vol 25, No 6, June 2016**

**25 ^{th} Anniversary Year of
AJP-2016**

**Accepted
papers: Vol 25, No 6, 2016**

**Special
Section on**

**“Static
and dynamic---cold atoms and molecules"**

*
*

*
Asian Journal of Physics*
Vol. 25 No 6 (2016)
00-00

**Dynamics of atomic and molecular solitary waves in
atom-molecular hybrid Bose-Einstein condensates coupled byMagnetic
Feshbach Resonance: Role of induced decays of Feshbach
Molecules**

Krishna Rai Dastidar, and Deb Shankar Ray

*Indian
Association for the Cultivation of Science, Kolkata-700 032,
India*

*_*___________________________________________________________________________________________________________________________________

Dynamics
of atomic and molecular bright solitons in a hybrid atom-molecular
BEC (Bose Einstein Condensate) system of ^{85}Rb coupled
through Magnetic Feshbach Resonance (MFR) has been investigated. By
solving the time independent atom-molecular coupled
equations, the initial atomic and molecular wavefunctions were
obtained and the dynamics of the initial atomic and molecular waves
in a spherical one-dimensional trap were studied by solving the
time-dependent atom-molecular coupled equations. During evolution
two types of induced or stimulated decays of the feshbach molecules
were switched on. These two types of stimulated decays of the
feshbach molecules (i) to the two-atom continuum and (ii) to the
bound level of the lowest hyperfine state of the molecule were
induced by laser/RF (Radio Frequency) fields. Hence the strength of
these two induced decays can be controlled by varying the laser/RF
field parameters e.g. intensity, detuning etc. It is found that
depending on the relative strength of these two types of stimulated
or induced decays initial atomic and molecular waves assume
solitonic nature as bright solitons during evolution and the
stability of these solitonic waves can be achieved by controlling
the relative strength of induced decays in two different channels.
It is shown that these two induced decays lead to the formation of
stable atomic and molecular solitons by suppressing the initial
oscillations and instability in the atom-molecular coupled system
of 85Rb atoms. ©
Anita Publications. All rights reserved.

**
Total Refs: 52**

**
___________________________________________________________________________________________________________________________________**

*Asian Journal of
Physics*
Vol. 25 No 6 (2016)
00-00

** **

**Dispersion coefficients for the interaction of inert gas
atoms with alkali and alkaline earth ions
and **

**alkali atoms with their singly ionized
ions**

**
**

Sukhjit
Singh^{a}, KiranpreetKaur^{a}, B K
Sahoo^{b*} and Bindiya Arora^{a}

^{
a}*Department of Physics, Guru Nanak Dev University,
Amritsar, Punjab-143 005, India*

^{
b}*Theoretical Physics Division, Physical Research
Laboratory, Navrangpura, Ahemadabad-380 009, India*

___________________________________________________________________________________________________________________________________

We report the dispersion coefficients for the interacting inert gas atoms with the alkali ions, alkaline earth ions and alkali atoms with their singly charged ions. We use our relativistic coupled-cluster method to determine dynamic dipole and quadrupole polarizabilities of the alkali atoms and singly ionized alkaline earth atoms, whereas a relativistic random phase approximation approach has been adopted to evaluate these quantities for the closed-shell configured inert gas atoms and the singly and doubly ionized alkali and alkaline earth atoms, respectively. Accuracies of these results are adjudged from the comparison of their static polarizability values with their respective experimental results. These polarizabilities are further compared with the other theoretical results. Reason for the improvement in the accuracies of our estimated dispersion coefficients than the data listed in [At. Data and Nucl.Data Tables 101, 158 (2015)] are discussed. Results for some of the atom-ion interacting systems were not available earlier, these results and the other reported improved results will be very useful for the comprehensive understanding of the collisional physics involving these atom-atom and atom-ion interactions in the cold atom and atom-ion hybrid trapping experiments at the low-temperature regime.© Anita Publications. All rights reserved.

**
Total Refs: 60**

- Dispersion coeffcients for the interaction of inert gas atoms with....pdf
- Sukhjit Singh, Kiranpreet Kaur, B K Sahoo and Bindiya Arora

*Asian Journal of Physics*
Vol.
25 No 6 (2016) 00-00

** **

**A method to solve nonlinear Schrodinger equation using
Riccati equation**

Vivek
M Vyas^{1}, Rama Gupta^{2}, C N Kumar^{3}
and Prasanta K Panigrahi^{4}

^{
1}*Chennai Mathematical Institute, SIPCOT IT Park,
Siruseri- 603 103, India*

^{
2}*Department of Physics, DAV University, Jalandhar-
144 008, India*

^{
3}*Department of Physics, Panjab University,
Chandigarh- 160 014, India*

^{
4}*Indian Institute of Science Education and Research
Kolkata, Mohanpur, Nadia- 741 246, India*

___________________________________________________________________________________________________________________________________

A method to find exact solutions to nonlinear Schrodinger equation, defined on a line and on a plane, is found by connecting it with second order linear ordinary differential equation. The connection is essentially made using Riccati equation. Generalisation of several known solutions is found using this method, in case of nonlinear Schrodinger equation defined on a line. This method also yields non-singular and singular vortex solutions, when applied to nonlinear Schrodinger equation on a plane.© Anita Publications. All rights reserved.

**
Total Refs: 23**

*Asian Journal of Physics
*Vol
25, No 6, (2016) 00-00

** Experimental and DFT vibrational spectra and
structure of 3-Iodopyridine**

Nandini V. Aralikatti ^{‡} , J. Tonannavar
^{†}, Jayashree Yenagi ^{†*}

^{†}*Vibrational Spectroscopy Group,
Department. of Physics*

* Karnatak University, Dharwad-580003,
India*

^{ ‡}*Department. of
Physics, Kittel Science College, **Dharwad-580001,
India*

A complete review and reassignment of the vibrational spectra of
3-Iodopyridine have been proposed. The measured vibrational spectra
include IR (3500 – 400 cm^{-1}) and Raman (3500–100
cm^{-1}) spectra. Geometry and harmonic vibrational
frequencies of 3-Iodopyridine have been computed by employing a
batch of four density functional theoretical methods(DFTs) - *ab
initio* RHF, hybrid - B3LYP, B3PW91 and MP2 methods using the
LANL2DZ basis set. Analysis has shown that some vibrational modes
of 3-Iodopyridine change both in intensity and frequency with
respect to Pyridine, mono-substituted halo-pyridines including
2-Iodopyridine. Absence of two characteristic C-H stretching modes
near 3069 and 3051cm^{-1} as IR and Raman bands is
attributed to the weakening of the *sp ^{2}*
hybridization in the pyridine ring. The C-H bending modes near 1450
-1400 cm

Keywords: 3-Iodopyridine, IR, Raman, B3LYP, B3PW91, MP2, LANL2DZ

**
Total Refs: 29**

*Asian Journal of Physics
*Vol
25, No 6, (2016) 00-00

**
**

**
Gravitation and Radiation**

Francis T S Yu

*Emeritus Evan Pugh Professor of Electrical
Engineering*

*Penn State University, University Park, PA 16802,
USA*

Gravitation is one of the most intriguing forces in space that govern all the interstellar spectacles motion in this universe. In this article we have shown there is a profound relationship between gravitational fields with respect to its converted energy. Since time is an inevitable element in every aspect of science; we have developed a partial differential equation from Einstein’s energy equation in which we show that gravitational field can be coupling with its diverging energy radiation. We have also shown that energy to mass conversion in principle is conceivable by means of energy convergent operation (i.e., in-flow) into a unit space. In fact this could have been happen by the eventuality of a black hole explosion, as remains to be observed. .©Anita Publications. All rights reserved.

** Keywords:** Gravitation, Interstellar
spectacles, Einstein’s energy equation, Black hole

**
Total Refs: 11**

*Asian Journal of Physics
*Vol
25, No 6, (2016) 00-00

**
Cold ion based geometric phase generation: a tool or non-optical
quantum computation**

Debashis De Munshi

*Centre
for Quantum Technologies, National University of Singapore,
Singapore - 117543*

* *Manas
Mukherjee

Centre for Quantum Technologies, National University of Singapore, Singapore - 117543 and

Department of Physics, National University of Singapore, Singapore - 117551

Abelian and Non-Abelian evolution of a quantum system manifests differently in the geometric phase acquired by the system under such evolutions. In this work, we develop the theory and study the properties of a experimentally realizable spin system which can be driven continuously from Abelian to non-Abelian geometry and vice versa. This unified framework allows us to characterize the parameter dependence of the geometric phase originating from different geometry of the Hilbert space. As geometric phase is key to robust quantum computation, we quantify the noise related to geometric phase and its dependence on external parameters. As a consequence we find the noise to be entirely dependent on the geometry of the system. © Anita Publications. All rights reserved.

**Total
Refs: 18**

*Asian Journal of Physics
*Vol
25, No 6, (2016) 00-00

**Bosons in a trap: phases and dynamics**

K Sengupta

*Theoretical
Physics Department, Indian Association for the Cultivation of
Science, Jadavpur, Kolkata*

We review a hopping expansion technique for studying phases and phase transition of strongly interacting bosons in an optical lattice in the presence of a harmonic trap. The advantage of this technique is that it allows one to study both the equilibrium phase diagram and non-equilibrium dynamics of the bosons at same footing. The technique also enables one to treat quantum fluctuations of the bosons systematically and leads to a the boson phase diagram which is almost as accurate as that found by quantum Monte Carlo. In addition, it predicts several novel non-equilibrium effects which are missed by mean-field theory. © Anita Publications. All rights reserved.

**Keywords:**
Bosons; Phase transition; Monte Carlo

**Total
Refs: 29**

*Asian
Journal of Physics
*Vol
25, No 6, (2016) 00-00

**Two-photon photoassociation of a pair of interacting atoms
in a trap**

Partha
Goswami^{1}, Arpita Pal^{1}, Subrata
Saha^{1} and Bimalendu Deb^{1;2}

^{
1}*Department of Materials Science,*

*Indian
Association for the Cultivation of Science* (*IACS),
Jadavpur, Kolkata-700 032, India,*

^{
2}*Raman Centre for Atomic, Molecular and Optical
Sciences,*

*IACS,
Jadavpur, Kolkata-700 032, India.*

We show that it is possible to generate coherent coupling between the discreet eigenstates of a pair of interacting atoms in a trap by two-photon photoassociation, via adiabatic elimination of the excited molecular state involved in the PA transitions. We develop a fully quantum mechanical treatment of the problem and present a dressed state description for the eigenstates. This coherent coupling is important for manipulating the relative motional states of the two atoms. © Anita Publications. All rights reserved.

**Keywords**:
Photoassociation (PA);Ultracold atoms; Coherent coupling

**Total
Refs: 29**

*Asian Journal of Physics
*Vol
25, No 6, (2016) 00-00

**Vibrational study of Azobenzene: Comparative study with
ab-initio calculation**

Th.Gomti Devi

*Department
of Physics, North-Eastern RegionalInstitute of Science and
Technology*,

*Arunachal
Pradesh-791 109*, *India*

Azobenzene
is a photochromic molecule which exhibits a reversible
isomerisation process between its *trans* and *cis*
isomers of different stability. An investigation has been conducted
of the effects of temperature on intensity and position of Raman
bands of N=N and C-N stretching mode of Azobenzene (AZBN). It was
found that both the N=N stretching and the C-N stretching mode of
Raman band shape shifts to lower frequency region with the increase
in temperature. Ab initio calculation for geometry optimization and
vibrational wavenumber calculation have been performed to support
the experimental findings. © Anita Publications. All
rights
reserved.

Key
words : Azobenzene, isomerisation, IR and Raman spectra
*ab***-**initio

Total Refs: 22

*Asian Journal of Physics
*Vol
25, No 6, (2016) 00-00

**Molecular structure, spectroscopic (FT-IR, FT-RAMAN),
HOMO-LUMO, NMR,**

**and MEP analysis of
methyl- m-toluate**

I Sehar
^{a}, V Krishnakumar^{b} and S
Sivakumar^{c}

^{a}*Department
of Physics*, *Aditanar College of Arts and Science*,
*Tiruchendur – 628 215, India*

^{
b}*Department of Physics, Periyar University, Salem -
636 011, India*

^{
c}*Department of Physics, Govt. Arts College, Salem -
636 007, India*

The
FT-IR and FT-Raman spectra of methyl-*m*-toluate (MMT)
molecule were recorded in the range 4000–400 cm^{-1} and
4000–100 cm^{-1}, respectively at room temperature. The
molecular structure, fundamental vibrational frequencies and
intensity of the vibrational bands were interpreted with the aid of
structure optimizations and normal coordinate force field
calculations based on density functional theory (DFT) method. The
complete vibrational assignments of frequencies were made on the
basis of potential energy distribution (PED). The scaled
B3LYP/6-311+G** calculated results agreed well with the
experimental values. The calculated HOMO and LUMO energies revealed
that the charge transfer occurred within the molecule. Moreover,
HOMO-LUMO energy gap related properties such as ionization
potential, electron affinity, global hardness, global softness,
chemical potential and electrophilicity index were calculated. The
effects due to the substitution of methyl groups were also
investigated. The calculated results from B3LYP/6-311+G** were
applied to simulate the spectra of the title compound, which showed
excellent agreement with the experimental spectra. Furthermore,
Natural Bonding Orbital (NBO) analysis was done and stabilization
energies E^{(2)} were calculated. The change in electron
density (ED) in the orbital and molecular electrostatic potential
(MEP) were analyzed. © Anita Publications. All rights
reserved.

Key
words: FT-IR and FT-Raman spectra, MEP, HOMO-LUMO,
DFT.

*Asian Journal of Physics
*Vol
25, No 6, (2016) 00-00

**Integration of phoneme pattern recognition with hidden
Markov models to enhance**

**performance of low level speech
recognition**

Mohammed Al-Darkazali, Rupert Young, and Chris Chatwin, Phil Birch

*School
of Engineering and Informatics, 2B09, Shawcross building, Brighton
BN1 9QT 43, U K*

The hidden Markov model (HMM) is commonly employed in automatic speech recognition (ASR). The HMM has been shown to have a good performance in many applications, although it has some well-known limitations in modelling speech. Therefore, the standard HMM topology has been modified in a variety of ways to reduce errors, including factorization of the HMM into multiple-streams. However, the gap between the theoretical representation of speech and its acoustic representation can be further reduced. This paper describes a new method of correcting the HMM based on matching two dimensional templates of word time-frequency patterns to assist in low level speech recognition (Pl correct sentence construction). This is shown to be a promising method to enhance speech recognition performance. © Anita Publications. All rights reserved.

**
Keywords:** Pattern matching, image matching, hidden
Markov models, automatic speech recognition.

Total Refs: 17

*© ANITA
PUBLICATIONS*

*All rights
reserved*