Solid State Physics Laboratory

About: Solid State Physics Laboratory is a facility organization based out in Delhi, India. It is known for research contribution in the topics: Quantum dot & Dielectric. The organization has 1754 authors who have published 2597 publications receiving 50601 citations.

Study of Lead Magnesium Niobate–Lead Titanate Ceramics for Piezo-Actuator Applications

Abstract: Structural, dielectric, ferroelectric and piezoelectric properties of lead magnesium niobate–lead titanate, PMN–PT (66:34), prepared at different sintering temperatures (1150–1250°C) are discussed for actuator applications. System sintered at 1200 and 1250°C showed better perovskite phase stabilization and higher values of dielectric constant (er). Remnant polarization (Pr) was found to be higher (45 µC/cm2) for the system sintered at 1250°C. The piezoelectric coefficients, d33, d31, dh and strain induced in the system by a large electric field were found to be sintering temperature dependent. Hysteresis free strain behavior of the system sintered at 1200°C showed the suitability of this material for actuator applications.

Transversely excited 337 μm HCN waveguide laser.

Abstract: Theory, construction and performance of the first transversely excited HCN 337 μm waveguide laser are presented. The first part of this paper reviews the theory of the particular waveguide structure. Losses, fields and resonance conditions are calculated with the Maxwell equations by analytical approximation.

Coexistence of Interfacial Stress and Charge Transfer in Graphene Oxide based Magnetic Nanocomposites

Abstract: In this paper, we establish the existence of both compressive stress and charge transfer process in hydrothermally synthesized cobalt ferrite-graphene oxide (CoFe2O4/GO) nanocomposites. Transmission electron microscopy (TEM) results reveal the decoration of CoFe2O4 nanoparticles on GO sheets. Magnetic response of nanocomposites was confirme from superconducting quantum interference device (SQUID) magnetometer measurement. Optical properties of these nanocomposites were investigated by Raman spectroscopy. Interfacial compressive stress involved in this system is evaluated from observed blue shift of characteristic G peak of graphene oxide. Increase in full width half-maximum ( FWHM) as well as up shift in D and G peaks are clear indicator of involvement of charge transfer process between GO sheets and dispersed magnetic nanoparticles. The effect of charge transfer process is quantified in terms of shifting of Fermi level of these nanocomposites. This is evaluated from variation in contact surface potential difference (CPD) using Scanning Kelvin probe microscopy (SKPM). XRD spectra of CoFe2O4/GO confirm the polycrystalline nature of CoFe2O4 nanoparticles. Lattice strain estimated from XRD peaks are correlated to the observed Raman shift.