Now showing items 1-10 of 42
A thermodynamic cycle for the solar cell
A solar cell is a heat engine, but textbook treatments are not wholly satisfactory from a thermodynamic standpoint, since they present solar cells as directly converting the energy of light into electricity, and the current ...
Quantum ferroelectric instabilities in superconducting SrTiO3
We examine the effects of strain and cation substitution on the superconducting phase of polar semiconductors near a ferroelectric quantum phase transition with a model that combines a strong coupling theory of ...
Why is the electrocaloric effect so small in ferroelectrics?
Ferroelectrics are attractive candidate materials for environmentally friendly solid state refrigeration free of greenhouse gases. Their thermal response upon variations of external electric fields is largest in the vicinity ...
Relation between Luminescence and Electronic Surface Characteristics in p-type Porous Silicon
Measurements of photoluminescence, electronic surface states and effective surface area, at various stages of the anodization process, are presented. The results show a behavior different from that observed on n-type porous Si.
Diﬀerent stages of evolution of prominence and the associated CMEs
We study the diﬀerent evolutional stages of a large quiescent prominence, mainly considering its dynamic/thermal instabilities occurred close from the boundary of coronal hole (CH). We identify the critical conditions, ...
Exact solution of an ekpyrotic fluid and a primordial magnetic field in an anisotropic cosmological space-time of Petrov D
This document obtained and analyzed an exact solution of an ekpyrotic fluid (P = 5/3 µ) and a primordial magnetic field, so that the latter does not induce currents or electric fields. It is determined that the main role, ...
Large isotropic negative thermal expansion above a structural quantum phase transition
Perovskite structured materials contain myriad tunable ordered phases of electronic and magnetic origin with proven technological importance and strong promise for a variety of energy solutions. An always-contributing ...
The Hubble Constant and the Deceleration Parameter in Anisotropic Cosmological Spaces of Petrov type D
In this paper the Hubble parameter and the deceleration parameter are analyzed for a group of anisotropic homogeneous solutions of the Petrov type-D. It is obtained that for the said set of solutions can be constructed a ...
Tropical precipitation anomalies and d‐excess evolution during El Niño 2014‐16
The last 2014-16 El Niño event was among the three strongest episodes on record. El Niño considerably changes annual and seasonal precipitation across the tropics. Here, we present a unique stable isotope data set of daily ...
Interaction of a quantum field with a rotating heat bath
The linear coupling of a rotating heat bath to a quantum field is studied in the framework of the Markovian master equation for the field's non-unitary time evolution. The bath's rotation induces population inversion for ...