Indian Journal of Pure and Applied Physics

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Volume 47

Number 5

MAY 2009

CODEN: IJOPAU 47 (5) 321-390

ISSN: 0019-5596

 

 

       CONTENTS

The Physics of Elementary Particles and Fields

 

Pair distribution function for interacting bosons and the ground –state energy of solid helium-4

325

K M Khanna*, Y K Ayodo, T W Sakwa, S K Rotich, P K Torongey & W S Mbugua

 

Atomic and Molecular Physics

 

Growth and spectroscopic studies of L-argininum formate NLO single crystals

332

S Janarthanan, T Kishore Kumar, S Pandi & D Prem Anand*

 

Theoretical analysis of EXAFS data of copper (II) complexes of isoxezol series

337

Ashutosh Mishra*, Neetu Parsai & N Dagonkar

 

Semi-empirical method for obtaining Sommerfeld screening parameter σ1 in X-ray spectra

340

U D Misra* & S Chaturvedi

 

Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics and Fluid Dynamics

 

Optical communication using chaos based signal transmission scheme

346

G Kandiban & V Balachandran*

 

Physics of Gases, Plasmas and Electric Discharges

 

Study on kinetic Alfven wave in inertial regime

350

Nidhi Shukla, P Varma & M S Tiwari *

 

Condensed Matter: Structural, Mechanical and Thermal Properties

 

Growth of KTiOPO4 crystals by flux technique and their characterization

356

E Gharibshahian , M J Tafreshi*& M Fazli

 

Elastic properties of intermetallic compounds under high pressure and high temperature

362

A K Upadhyay* & B S Sharma

 

 

 

Growth and characterization of NLO crystal

369

R Ananda Kumari

 

Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties

 

Polarization-tilt coupling for surface stabilized ferroelectric liquid crystal

372

Surjya Sarathi Bhattacharyya, A Mukherjee, B K Chaudhuri* & S L Wu

 

Structural and luminescence properties of sol-gel derived Cu doped ZnO films

377

K Das, S Ray, S Chaudhuri   & A B Maity*

 

Dielectric relaxation studies of ternary liquid mixtures of aniline and substituted anilines with
acrylonitrile in the microwave region

383

T Kalaivani* & S Krishnan

 

 

 

__________

*The corresponding author has been indicated by (*) mark in case of papers with more than one author

 

 

 

 

 

 

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 325-331

 

 

Pair distribution function for interacting bosons and the
ground-state energy of solid helium-4

 

K M Khanna1, Y K Ayodo2, T W Sakwa2, S K Rotich1, P K Torongey1 & W S Mbugua1

1Department of Physics, Moi University, Box 1125 Eldoret-Kenya

2Department of Physical Sciences, Masinde Muliro University of Science & Technology, Box 190, Kakamega-Kenya

Received 14 October 2008; revised 12 February 2009; accepted 9 March 2009

The pair distribution function g(r) for a system of bosons interacting through a two-body potential composed of a hard core followed by a square well has been obtained using the reaction matrix formalism for the energy excitation spectrum Ek and the fundamental definition relating the structure factor S(k) and g(r) . This has been used in obtaining the ground state energy of solid 4He using the kinetic energy and potential energy expressions of Hansen and Levesque. The most stable ground state of solid 4He corresponds to a potential width of b=3.8Ǻ ,but the corresponding áEñ/N for the density, ρ, of solid 4He is very large compared with the experimental value. However, for b =4.81Ǻ and r=2.8×1022 particles/ cm3,
áEñ/N =-11.24 K= -93.4Joule/mol. and for b=4.82Ǻ  and r=2.5×1022 particles/cm3, áEñ/N = -6.84 K=56.8 Joule/mol. The experimental value for the ground state energy of solid 4He =-59.5J/mol.

Keywords: Bosons, Solid helium-4, Ground-state energy

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 332-336

 

 

Growth and spectroscopic studies of L-argininum formate NLO single crystals

S Janarthanan, T Kishore Kumar, S Pandi & D Prem Anand*

Department of Physics, Presidency College, Chennai 600 005

*Department of Physics, St. Xavier’s College, Palayamkottai 627 002

Received 1 November 2008; revised 6 February 2009; accepted 4 March 2009

Non-linear optical (NLO) organic crystals of L-argininum formate (LAF) have been grown using low temperature solution growth technique. The cell parameters of the crystal were determined using single crystal X-ray diffraction analysis. FTIR analysis was done to confirm the presence of various functional groups in the LAF crystalline sample. FT–Raman analysis carried out on LAF ascertained the presence of formate ion in the crystal lattice. H1 NMR spectral analysis revealed its structural identification. The surface morphology of the grown crystal was studied using SEM analysis.

           Keywords: Solution growth, LAF, Scanning electron microscope, Single crystals, Non-linear optical crystal.

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 337-339

 

 

Theoretical analysis of EXAFS data of copper (II) complexes of isoxezol series

Ashutosh Mishra1, Neetu Parsai1 & N Dagonkar2

1School of Physics, Devi Ahilya University, Khandwa Road, Indore 452 001

2Physics Department, Govt P G College, Dhar 457 001

Received 4 August 2008; revised 26 December 2008; accepted 20 February 2009

A newly approached method has been employed for analysis of the K-absorption X-ray spectra of mixed ligand complexes and verification of structural parameters obtained experimentally. Extended X-ray absorption fine structure (EXAFS) data is generated using standard EXAFS equation and EXAFS curves are plotted for some copper (II) mixed ligand complexes of isoxezol series. Fourier transform of calculated EXAFS data has been taken to calculate bond lengths theoretically. These bond lengths are compared with bond lengths obtained using other methods from experimental EXAFS data. Imaginary part of Fourier transform is compared with the amplitude of Fourier transform to verify consistency of experimentally obtained phase shift parameter with calculated data.

Keywords: EXAFS, Copper (II) mixed ligand complexes, Isoxezol series, Fourier transform

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 340-345

 

   

Semi-empirical method for obtaining Sommerfeld screening parameter σ1
in X-ray spectra

U D  Misra & S  Chaturvedi

Physics Department , Lucknow University, Lucknow 226 007

Received 28 March 2008; revised 2 February 2009; accepted 12 February 2009

The present method is an effort to reduce the requirement of the amount of input data for the calculation of the screening parameter s1. The method requires the knowledge of no other data except the energy value of the level for the element under consideration. The fresh calculations of the screening parameter σ1 using the new method for the levels L1, L2L3, M1, M2M3, M4M5, N1, N2N3 and N4N5 in the atomic numbers range Z=57 to Z=71, have been described in the present paper. 

Keywords:   Screening parameter, Spin doublets, Experimental energy values, Sub shell, Inner shell filling and closure,

                        Hertz law

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 346-349

 

 

Optical communication using chaos based signal transmission scheme

G Kandiban 1 & V Balachandran 2,*

1Department of Physics, Thanthai Hans Roever College, Perambalur 621 212

2Department of Physics, A A Government Arts College, Musiri, Tiruchirappalli 621 201

*E-mail: brsbala@rediffmail.com

Received 11 February 2008; revised 16 February 2009; accepted 20 March 2009

Optical communication system using a chaos based signal transmission scheme has been proposed to transmit digital information signal by using the conventional synchronization of chaos and digital transmission approaches. In this scheme either a chaotic or hyper chaotic system is used to generate a chaotic signal. This signal along with the information digital signal is used to generate the transmitted signal. The transmitted signal is then masked by one of the chaotic signal of the transmitter and is transmitted through the channel to the receiver as well as used to drive the transmitter chaotic system using the concept of self-modulation. At the receiver end, suitable subtractor circuit is constructed for unmasking and the reception rule is used to recover the information signal. The effect of typical perturbing factors like channel noise and parameter mismatch are also included and their corresponding performance analysis has been done. By considering appropriate circuit configuration, the results of experiment are also presented.

Keywords: Optical communication, Chaotic modulation, Signal transmission, Performance analysis

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 350-355

 

 

Study on kinetic Alfven wave in inertial regime

 

Nidhi Shukla*, P Varma & M S Tiwari*

Department of Physics & Electronics, Dr H S Gour University, Sagar 470 003

*E-mail: tiwarims@rediffmail.com, poornimavarma@yahoo.com, nidhiphy.shukla@gmail.com

Received 28 August 2008; revised 31 December 2008; accepted 4 February 2009

The effect of electron inertia on kinetic Alfven wave (KAW) has been studied. The inertial Alfven waves propagating in regions of auroral electron acceleration are reported from the FAST spacecraft over its entire altitude range (350-4180), (e.g., Chaston et al., Physics Scripta, T84, (2000) 64). The Vlasov-kinetic theory has been adopted to evaluate the dispersion relation, damping rate and growth length, with respect to the normalized perpendicular wave number (k^c/wpe) with different plasma density. It is observed that inertial Alfven wave frequency (ω) is decreasing with (k^c/wpe)  and plasma density. The growth rate and growth length are evaluated for different (me/bmi), where b is the ratio of electron pressure to the magnetic field pressure, mi,e are the mass of ion and electron, respectively as b = me/bmi  represent boundary between the kinetic and inertial regimes. The effects of electron density on the wave frequency, growth rate and growth length are also given as the wave propagates towards higher density side of the lower ionospheric region. Although, the wave is highly damped, it requires longer distance of propagation as predicted by growth length. Thus, some another mechanism should also be operative to dissipate kinetic Alfven wave energy as the Landau damping mechanism alone is not sufficient due to higher growth length. The results show the scenario of auroral pattern in northern and southern hemisphere (Swift D W, J Geophys Res, 112 (2007) A12207). The significance of the investigation for the auroral acceleration region is also presented.

Keywords: Inertial Alfven wave, Auroral region, Acceleration, Growth length, Landau damping

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 356-361

 

 

Growth of KTiOPO4 crystals by flux technique and their characterization

E Gharibshahiana, M J Tafreshia* & M Fazlib

aPhysics Department, bChemistry Department, Faculty of Science, Semnan University, Semnan, Iran

Received  18 September 2008 ; revised 9 January 2009 ; accepted 12 March 2009

Single crystals of KTiOPO4 (KTP) have been grown by flux technique using K6P4O13 flux. Crystals up to 3×2×1 mm3 in size were grown by slow cooling and spontaneous nucleation when high temperature solution was cooled down to room temperature with the rate of 7°C/h. The structure and quality of the grown crystals were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Optical Transmission analysis. The surface morphology of the grown crystals was studied by scanning electron microscopy (SEM).

Keywords: Crystal growth, Non-linear optical materials, Flux growth, KTiOPO4, Characterization

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 362-368

 

 

Elastic properties of intermetallic compounds under high pressure and high temperature

A K Upadhyay* & B S Sharma

Department of Physics, Institute of Basic Sciences, Khandari, Agra

*E-mail: aupadhyay29@yahoo.in

Received 8 July 2008; revised 3 February 2009; accepted 12 March 2009

The elastic properties of intermetallic compounds MgB2, TiB2 and LiBC under high pressure and high temperature using the Hama-Suito theory of equation of state based on the augmented plane wave (APW) and quantum statistical methods have been studied. The results have been obtained for P-V-T relationship and isothermal bulk modulus at high temperature up to 1000K and down to compression of 50% (V/V0 = 0.50). The input parameters used in calculation are based on the first-principles method. The importance of extreme compression behaviour has been discussed in terms of the Thomas-Fermi model.

Keywords: Bulk modulus, Equation of state, High pressure, High temperature

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 369-371

 

 

Growth and characterization of NLO crystal

R Ananda Kumari

Department of Physics, Sree Siddaganga College for Women, Tumkur 572 101

E-mail: ranandakumari61@yahoo.com

Received 10 August 2008; revised 6 March 2009; accepted 30 April 2009

Pure ammonium dihydrogen orthophosphate (ADP) crystals and ADP crystals doped with nitrite tri-acetic acid and ethylene diamine tetra acetic acid (EDTA) have been grown by slow evaporation technique. Grown crystals have been characterized using X-ray diffraction and energy dispersive X-ray spectroscopy (EDAX). Second harmonic generation (SHG) efficiency measurements are carried out by Kurtz method. It has been found that the ADP crystals containing nitrite tri acetic acid and EDTA have resulted appreciable increase in SHG efficiency as compared to pure ADP crystals. Dielectric constant and dielectric loss are measured as a function of frequency. Study confirms the contribution of space charge polarization.

Keywords: ADP crystals, Second harmonic generation efficiency, Dielectric constant, Dielectric loss

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 372-376

 

 

Polarization-tilt coupling for surface stabilized ferroelectric liquid crystal

Surjya Sarathi Bhattacharyya, A Mukherjee, B K Chaudhuri* & S L Wu**

Department of Solid State Physics, Indian Association for the Cultivation of Science, Kolkata 700 032

**Department of Chemical Engineering, Tatung Institute of Technology, Taipei 104, Taiwan R O C

E-mail: sspbkc@rediffmail.com

Received 11 November 2008; revised 20 February 2009; accepted 26 March 2009

A ferroelectric liquid crystal (FLC) material in surface stabilized geometry has been characterized by polarized optical microscopic technique and detailed study of temperature dependent spontaneous polarization (PS) and tilt angle (q) have been carried out. The tilt angle (q) has been measured in a newly developed electro-optic method. The coupling coefficient between molecular polarization (PS) and tilt (q) has been determined in accordance with extended Landau theory.

Keywords: Ferroelectric liquid crystal, Electro-optic, Switching phenomenon

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 377-382

 

 

Structural and luminescence properties of sol-gel derived Cu doped ZnO films

 

K Dasa, S Raya, S Chaudhuria & A B Maityb

aDepartment of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032

b School of Applied Sciences, Haldia Institute of Technology, Haldia 721 657

E-mail: abm_hit@yahoo.com

Received 9 May 2008; revised 12 March 2009; accepted 30 April 2009

Well crystallized Cu doped (1, 3 and 5 molar %) ZnO films have been deposited on quartz substrates by sol-gel technique. The microstructural, optical and photoluminescence properties of the films have been studied. It has been observed that the band gap (3.38 eV) of ZnO films did not vary up to 5 molar % of Cu doping. The preferred orientation along (002) was observed for all the films. The X-ray diffraction (XRD) measurement confirmed the decrease of degree of orientation of (002) plane with increasing molar % of Cu in the films. The atomic force microscopy (AFM) measurements have also been performed to examine the surface morphologies of the films. It has been observed that the surface roughness of 1 molar % Cu doped film is smaller (~ 6 nm) than those of 3 and 5 molar % of Cu. The photoluminescence of the films shows prominent peaks between 2.27 to 3.11 eV due to excitonic as well as defect related transitions. A possible mechanism of carrier transitions between shallow and deep impurity levels in the photoluminescence has also been studied.

Keywords: Sol-gel, Cu doping, ZnO film, Microstructure, Photoluminescence

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, May 2009, pp. 383-385

 

 

Dielectric relaxation studies of ternary liquid mixtures of aniline and substituted anilines with acrylonitrile in the microwave region

T Kalaivani* & S Krishnan**

*Department of Physics, S R M University, Kattankulathur 603 203.

**Faculty of Engineering and Technology, Annamalai University, Annamalainagar, 608 002

*E-mail: tkv_p29@rediffmail.com

Received 26 November 2008; revised 20 February 2009; accepted 27 March 2009

Dielectric behaviour of three amines and their mixtures: N-methyl aniline + acrylonitrile, aniline+ acrylonitrile and N, N-dimethyl aniline + acrylonitrile at microwave frequency 9.36GHz has been studied at temperature 303K. Different dielectric quantities like dielectric constant (ε׳), dielectric loss (ε״), static dielectric constant (εo), and dielectric constant at optical frequency (ε) have been determined. The relaxation time (τ) has been calculated by both Higasi’s method and Cole-Cole method. The molar free energy of activation (ΔFτ) and (ΔFη) have also been calculated. The complex systems studied show the maximum relaxation time values at 1:1 complex ratio by both Higasi’s method and Cole-Cole plot method.

Keywords: Dielectric relaxation, Aniline, Acrylonitrile, Frequency domain technique.