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.

Mode spectroscopy and level coupling in ballistic electron waveguides

Abstract: A tunable quantum point contact with modes occupied in both transverse directions is studied by magnetotransport experiments. We find conductance quantization that can be suppressed by degeneracies of one-dimensional modes. The mode spectrum is determined as a function of the magnetic field of different orientations with respect to the quantum wire. A magnetic field applied parallel to the direction of the current flow couples the modes. This can be described by an extension of the Darwin-Fock model. Anticrossings are observed as a function of the parallel magnetic field, but not for zero field or perpendicular field directions, indicating coupling of the subbands due to nonparabolicity in the electrical confinement.

Multiphoton electron emission from Cu and W: An angle-resolved study

Abstract: The experimental results of multiphoton electron emission from Cu and W induced by 2-eV 100-fs laser pulses with $s$ and $p$ polarizations at incidence angles between 0\ifmmode^\circ\else\textdegree\fi{} and 85\ifmmode^\circ\else\textdegree\fi{} and different intensities are reported. The data show a third-order nonlinear photoemission process for Cu and a fourth-order behavior for W. For both metals the electron emission is higher for the polarization in the incidence plane, with a maximum value at the pseudo-Brewster angle, while the electron yield as a function of the incidence angle exhibits an unambiguous dependence on the bulk absorption coefficient and it can be accounted for on the basis of the Fresnel equations.

Dielectric, ferroelectric and pyroelectric properties of PMNT ceramics

Abstract: In the present study, different PMNT samples in the MPB range were prepared in single perovskite phase using Columbite technique. After poling, dielectric constant (er) of PMNT 70/30 samples decreases and of PMNT 68/32 and PMNT 66/34 samples increases. Polarization vs. electric field (P–E) hysteresis loops of PMNT samples show their ferroelectric nature. Transition temperature (Tc) obtained from pyroelectric coefficient ( p i ) variation with temperature increases with the increase in PT content in PMNT samples near MPB and agrees with Tc obtained from the dielectric study.