Department of Physics

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Flexibility in curriculum, in all its academic programs, encompassing elements of teaching, research, creativity, innovation and entrepreneurship is the most unique feature of IIT Jodhpur. The Department of Science and Technology (DST), under the National Mission on Cyber Physical Systems, has identified IIT Jodhpur as a Technology &amp; Innovation Hub in the area of Augmented Reality and Virtual Reality. The institute has also been nominated as the coordinator for the Jodhpur City and Knowledge Cluster by the Office of Principal Scientific Adviser, Government of India.

The sprawling 852-acre IIT Jodhpur campus is a majestic tribute to the deep-rooted diverse cultural heritage of the region. The campus is an architectural masterpiece, which is slated to become an international exemplar of sustainability with net-zero energy, and advanced water and waste management strategies.&rdquo;

IIT Jodhpur

World University root node

ICOPS/BEAMS 2014 - 41st IEEE International Conference on Plasma Science and the 20th International Conference on High-Power Particle Beams

Electrical and optical characterization of DBD based XeCl UV excimer source

In this paper, a cold cathode based sheet-beam plasma cathode electron gun is reported with achieved sheet-beam current density ∼1 kA/cm2 from pseudospark based argon plasma for pulse length of ∼200 ns in a single shot experiment. For the qualitative assessment of the sheet-beam, an arrangement of three isolated metallic-sheets is proposed. The actual shape and size of the sheet-electron-beam are obtained through a non-conventional method by proposing a dielectric charging technique and scanning electron microscope based imaging. As distinct from the earlier developed sheet beam sources, the generated sheet-beam has been propagated more than 190 mm distance in a drift space region maintaining sheet structure without assistance of any external magnetic field. © 2015 AIP Publishing LLC.

Fulltext

Review of Scientific Instruments

Experimental investigation of a 1 kA/cm2 sheet beam plasma cathode electron gun

FeVO4 is a multiferroic that undergoes two antiferromagnetic transitions at TN1∼21K and TN2∼15K, with a small ferroelectric polarization developing at the 15-K transition. We have studied the effect of magnetic and nonmagnetic transition metal dopants on these magnetic phase transitions in order to investigate the microscopic mechanisms for magnetoelectric coupling in this system as well as probing the evolution of the phase transitions. We have synthesized polycrystalline Fe1-xTMxVO4(TM=Zn,Cr,Mn) samples up to x=0.2 and studied dynamics of these two ferroic phase transitions using thermodynamic, magnetic, and pyrocurrent measurements. We find that the magnetic ordering temperatures in FeVO4 are remarkably stable, showing only a minimal suppression in transition temperatures even for larger doping fractions. We also observe clear reversible polarization at x=0.05 for all samples, which also persists to the largest doping for Zn, suggesting that the multiferroic order persists over a large range of compositions. © 2015 American Physical Society.

Physical Review B - Condensed Matter and Materials Physics

Effect of transition metal doping on multiferroic ordering in FeV O4

Using transient absorption spectroscopy we investigate the ultrafast dynamics of the electronic excited state of nitrogen-vacancy defects in diamond for temperatures 10K-300K, observing vibrational relaxation times of 40fs and temperature-dependent bi-exponential anisotropy dynamics related to electron motion between the Jahn-Teller-distorted orbitals. © OSA 2015.

CLEO: QELS - Fundamental Science, CLEO_QELS 2015

Ultrafast photo-excitation dynamics of nitrogen-vacancy defects in diamond

We present chalcogenide (Ch) glass-based all-fiber application-specific microstructured optical fibers (MOFs)-based devices like all-fiber efficient discrete and broad-band light sources as well as fibers for distortion free high power light guidance in the mid-IR spectral regime. For new source generation, nonlinearities and dispersion of index guided Ch-MOFs were suitably tailored through structural optimization, while for high power guidance, an ultra large mode area fiber design and a second design for distortion free parabolic pulse generation will be described. © Springer India 2015.

Springer Proceedings in Physics

Specialty optical fibers for Mid-IR photonics

This study deals with the exploration of CoFe2O4 supported Ag nanoparticles as a catalyst for the decolorization of various dyes (such as 4-nitrophenol, Congo red, rhodamine B) and dye mixtures by employing a reduction reaction with excess NaBH4 in an aqueous medium. Nanocatalysts with 10 wt% Ag loading (10Ag@CoFe2O4) exhibited very high catalytic activity and dye solutions were found to be decolorized within 4 to 6 minutes. A simple method for the preparation of a catalyst (10Ag@CoFe2O4) was reported, which exhibited very high catalytic efficiency towards the decolorization of dyes with different chemical structures as well as demonstrating its magnetic properties for easy separation from reaction mixtures and its reusability. © 2015 The Royal Society of Chemistry.

RSC Advances

Preparation of a magnetically separable CoFe2O4 supported Ag nanocatalyst and its catalytic reaction towards the decolorization of a variety of dyes

Biosensors and Bioelectronics

Different shades of cholesterol: gold nanoparticles supported on MoS2 nanoribbons for enhanced colorimetric sensing of free cholesterol

We focus on the probability distribution function (PDF) P(Δγ;γ) where Δγ are the measured strain intervals between plastic events in a athermal strained amorphous solids, and γ measures the accumulated strain. The tail of this distribution as Δγ→0 (in the thermodynamic limit) scales like Δγη. The exponent η is related via scaling relations to the tail of the PDF of the eigenvalues of the plastic modes of the Hessian matrix P(λ) which scales like λθ, η=(θ-1)/2. The numerical values of η or θ can be determined easily in the unstrained material and in the yielded state of plastic flow. Special care is called for in the determination of these exponents between these states as γ increases. Determining the γ dependence of the PDF P(Δγ;γ) can shed important light on plasticity and yield. We conclude that the PDF's of both Δγ and λ are not continuous functions of γ. In slowly quenched amorphous solids they undergo two discontinuous transitions, first at γ=0+ and then at the yield point γ=γY to plastic flow. In quickly quenched amorphous solids the second transition is smeared out due to the nonexisting stress peak before yield. The nature of these transitions and scaling relations with the system size dependence of (Δγ) are discussed. © 2015 American Physical Society.

Physical Review E - Statistical, Nonlinear, and Soft Matter Physics

Stochastic approach to plasticity and yield in amorphous solids

We studied magnetic properties of bulk LaCrO3; a GdFeO3-type distorted perovskite, with a predominant antiferromagnetic phase transition at ∼290 K. The bulk LaCrO3 exhibits intrinsic weak ferro magnetism at room temperature, which may arise due to the tilting of CrO6 octahedra, resulting in a non-zero net magnetic moment, as confirmed from the magnetization measurements. A broad magnetically-induced entropy change (-ΔS) is observed with the maxima at 290 K, close to room temperature in LaCrO3 system. © 2015 IOP Publishing Ltd.

Materials Research Express

Magnetostructural and magnetocaloric properties of bulk LaCrO3 system

In this paper, an effort has been made to study the recently developed pseudospark discharge-based 20 kV/200 A plasma cathode electron gun by using 3-D particle-in-cell simulation code VORPAL for discharge current analysis to validate the experiments. The experimental and simulation studies have been performed at different working pressures between 50 and 100 mTorr and at different applied voltages between 10 and 20 kV. Argon has been used as the working gas. The temporal behavior of the discharge current, discharge voltage, potential distribution within the hollow cathode region and the electron plasma density buildup has been analyzed from the simulations. The experiments have been performed to measure the dynamic nature of the discharge voltage and discharge current at different operating conditions. An agreement between the simulated and experimental results has been obtained well within 10 % for the discharge currents at different applied voltages, qualifying the design. © 2015, Indian Association for the Cultivation of Science.