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We report the single crystal growth of pyrochlore iridate Bi2Ir2O7 and its magnetic properties. The single crystals of Bi2Ir2O7 have been grown at 1150°C through the self-flux method. The crystals are found in octahedron-type shape with a typical size of ~340 µm. The Laue diffraction pattern suggests that the crystals of Bi2Ir2O7 are in a unique crystalline domain. Temperature-dependent zero-field and field-cooled magnetization data do not exhibit magnetic bifurcation down to 2 K and isothermal magnetization at 2K show a low moment 0.019 µB/f.u. [ABSTRACT FROM AUTHOR]

We report the single crystal growth of pyrochlore iridate Bi2Ir2O7 and its magnetic properties. The single crystals of Bi2Ir2O7 have been grown at 1150°C through the self-flux method. The crystals are found in octahedron-type shape with a typical size of ~340 µm. The Laue diffraction pattern suggests that the crystals of Bi2Ir2O7 are in a unique crystalline domain. Temperature-dependent zero-field and field-cooled magnetization data do not exhibit magnetic bifurcation down to 2 K and isothermal magnetization at 2K show a low moment 0.019 µB/f.u. [ABSTRACT FROM AUTHOR]

Measurements of excitation function (EF) for the evaporation residues populated via complete and incomplete fusion in interaction of projectile 16O with target 146Nd have been done. Stack foil activation technique has been employed for these measurements. The measured excitation functions of the four ERs 158Er (4n), 157Er(5n), 155Dy(α3n) and 153Dy(α5n) has been compared with statistical model code PACE-4. The present measurements show that the experimental excitation functions for xn-emission channels follow the PACE-4 predictions to a great extent, whereas, α-emission channels don't agree well and exhibits considerable enhancement from theoretical predictions. The enhancements may be ascribed to the break-up of projectile 16O resulting in incomplete fusion as PACE-4 considers only the complete fusion process. It has also been found that with increment in the projectile energy, probability of projectile break-up increases. Further, the comparison of present data with earlier measurements supports that the incomplete fusion contribution increases with the entrance channel mass asymmetry of the system, but differently for different projectiles. [ABSTRACT FROM AUTHOR]

To study the dependence of incomplete fusion on entrance channel parameters, the excitation functions of evaporation residues populated through complete and/or incomplete fusion in 19F + 154Sm system were measured at projectile energy range ≈ 4–6 MeV/nucleon The measured excitation functions were compared with theoretical model PACE-4 predictions. Analysis of measured data suggests the production of xn/pxn-channels via complete fusion, as these were satisfactorily reproduced by PACE-4 cross-sections, while, a significant enhancement in the cross-sections of α-emitting channels was found, which was attributed due to the incomplete fusion process. A systematic study suggests that the incomplete fusion contribution increases with the entrance channel mass asymmetry and coulomb factor. Further, a study on the breakup threshold suggests that the incomplete fusion contribution increases with decrease in the α-Q value of the projectile. These present results clearly show the effect of projectile structure on ICF dynamics along with other entrance channel parameters. [ABSTRACT FROM AUTHOR]

We have investigated self-focusing of a q-Gaussian laser beam in a relativistic plasma channel using exponential density based transition. The present paper is devoted to the importance of using a ramp density profile in decreasing the beam width parameter considerably. The preference of ramp type plays a better role in guiding the high intensity laser pulses to several Rayleigh lengths. Our results obtained from numerical analysis show that laser self-focusing can be controlled by varying laser intensity parameter, q-values and suitable density ramp parameter. We have derived the nonlinear differential equation for the beam width parameter using WKB and Paraxial ray approximation and solved it numerically using the Runge Kutta method to study the nature of self-focusing and defocusing. It is observed that self-focusing of q-Gaussian laser beam can be increased with increasing laser intensity parameter. Moreover, in case of q-Gaussian laser beam, it is easier to focus lower q-values using suitable type of plasma density ramp. [ABSTRACT FROM AUTHOR]

The paper deals with the Structural properties on Mn, Co doped oxides ZnO samples using XRD, Positron Annihilation Lifetime (PAL) Spectra and Raman Spectra. The Mn, Co doped ZnO samples crystallize in a wurtzite structure without any impurity phases in XRD Spectra. The defect state of these samples has been investigated by using positron annihilation lifetime (PAL) spectroscopy technique in which all the relevant lifetime parameters are measured for all the spectra. The results are explained in the direction of doping concentration in these samples in terms of defects structure on Zn lattice site VZn and oxygen defects Vo. [ABSTRACT FROM AUTHOR]

We have studied the effect of site dilution with substitution of nonmagnetic element at Ir-site in pyrochlore iridate Y2Ir2O7. Structural investigation has been done using x-ray powder diffraction and Rietveld analysis for both samples. No structural phase transition is observed with Ti doping. Magnetization data shows onset of magnetic irreversibility around temperature Tirr = 160 K in Y2Ir2O7, however, on slightly substitution of Ti at Ir-site slightly shifts down the magnetic irreversible temperature Tirr and reduces the bifurcation between MZFC and MFC branches. Above Tirr, a perfect Curie-Weiss behavior is observed for all samples. The magnetic isotherm and related Arrott plot analysis for both materials show an absence of ferromagnetic phase. [ABSTRACT FROM AUTHOR]

We have studied the effect of site dilution with substitution of nonmagnetic element at Ir-site in pyrochlore iridate Y2Ir2O7. Structural investigation has been done using x-ray powder diffraction and Rietveld analysis for both samples. No structural phase transition is observed with Ti doping. Magnetization data shows onset of magnetic irreversibility around temperature Tirr = 160 K in Y2Ir2O7, however, on slightly substitution of Ti at Ir-site slightly shifts down the magnetic irreversible temperature Tirr and reduces the bifurcation between MZFC and MFC branches. Above Tirr, a perfect Curie-Weiss behavior is observed for all samples. The magnetic isotherm and related Arrott plot analysis for both materials show an absence of ferromagnetic phase. [ABSTRACT FROM AUTHOR]

Experiment has been performed to explore the complete and incomplete fusion dynamics in heavy ion collisions using stacked foil activation technique. The measurement of excitation functions of the evaporation residues produced in the 20Ne +165Ho system at projectile energies ranges = 4-8 MeV/nucleon have been done. Measured cumulative and direct cross-sections have been compared with the theoretical model code PACE-2, which takes into account only the complete fusion process. The analysis indicates the presence of contributions from incomplete fusion processes in some a-emission channels following the break-up of the projectile 20Ne in the nuclear field of the target nucleus 165Ho. [ABSTRACT FROM AUTHOR]

We report the structural and magnetic properties of pyrochlore iridate Y2Ir2O7. Magnetic measurements show irreversibility in zero-filed-cooled and field-cooled data with an onset temperature around Tirr ~160 K. The magnetic isotherm and related Arrott plot analysis, however, imply an absence of ferromagnetic phase. The system retains its structural symmetry down to low temperature as seen from temperature dependent XRD measurement. Material shows significant magnetic relaxation at low temperature which implies a glass-like behavior in this system. [ABSTRACT FROM AUTHOR]

We report the structural and magnetic properties of pyrochlore iridate Y2Ir2O7. Magnetic measurements show irreversibility in zero-filed-cooled and field-cooled data with an onset temperature around Tirr ~160 K. The magnetic isotherm and related Arrott plot analysis, however, imply an absence of ferromagnetic phase. The system retains its structural symmetry down to low temperature as seen from temperature dependent XRD measurement. Material shows significant magnetic relaxation at low temperature which implies a glass-like behavior in this system. [ABSTRACT FROM AUTHOR]

We have studied the structural, magnetic, and electronic transport properties of pyrochlore iridate Pr2Ir2O7. Structural investigation has been done using x-ray powder diffraction and Rietveld analysis. Pr2Ir2O7 crystallize in cubic crystallographic phase with Fd-3m space group. Temperature dependent magnetization data does not show magnetic bifurcation down to 2 K. Electrical resistivity data of Pr2Ir2O7 exhibits metallic behavior throughout temperature range. Below 50 K, a small rise in resistivity data of Pr2Ir2O7 is observed down to 12 K. [ABSTRACT FROM AUTHOR]

We have investigated the electronic transport 5d based perovskite SrIrO3(SIO) thin films grown on SrTiO3(100) and LaAlO3(100) substrate by using Pulsed laser deposition method and studied the effect of compressive strain on electronic transport. SrIrO3 is strong spin orbit coupled weak correlated metal that shows various physical properties under external stimuli. In contrast to bulk, Transport measurement of SIOfilms shows insulating behavior. Temperature dependence resistivity fitting shows that electrical resistivity follows Mott variable-range hopping equation. Strong spin orbit interaction plays a crucial role in the transport property of SIO. [ABSTRACT FROM AUTHOR]

We have studied the structural, magnetic, and electronic transport properties of pyrochlore iridate Pr2Ir2O7. Structural investigation has been done using x-ray powder diffraction and Rietveld analysis. Pr2Ir2O7 crystallize in cubic crystallographic phase with Fd-3m space group. Temperature dependent magnetization data does not show magnetic bifurcation down to 2 K. Electrical resistivity data of Pr2Ir2O7 exhibits metallic behavior throughout temperature range. Below 50 K, a small rise in resistivity data of Pr2Ir2O7 is observed down to 12 K. [ABSTRACT FROM AUTHOR]