Band structure basically tells us the exact quantum mechanical description of the electrons, and in principle all properties of solids can be calculated from it. The quantum mechanical solution is nothing but the wave functions of the ‘allowed’ electronic eiganstates. So, an electron in an eiganstate will ideally extend throughout the sample. In another words, the electron is everywhere in spac...

For finite systems, the real part of the conductivity is usually decomposed as the sum of a zero frequency delta peak and a finite frequency regular part. In studies with periodic boundary conditions, the Drude weight, i.e., the weight of the zero frequency delta peak, is found to be nonzero for integrable systems, even at very high temperatures, whereas it vanishes for generic nonintegrable sy...

The electron diffusion and transport within the TiO2 network affect directly the device performance and, therefore, these phenomena have been studied over the past decades using different techniques and different charge transport models, such as Drude’s, and modified Drude’s models or effective medium theory. Here we employed optical pump THz probe spectroscopy (OPTP) to monitor the temporal ev...

The electrodynamic response of the heavy fermion compound CeCoIn5 is studied via infrared spectroscopy. Below 100 K the high temperature Drude-like conductivity evolves into two distinct components. At low energies a narrow mode is observed which is characteristic of the response of heavy quasiparticles. At higher energies a gap structure emerges with 2D;600 cm ~75 meV!. Examination of the fine...

We discuss the spectral, transport and magnetic properties of quantum nanowires composed of N 6 13 atoms and containing either even or odd numbers of valence electrons. In our approach we combine Exact Diagonalization and Ab Initio calculations (EDABI method). The analysis is performed as a function of the interatomic distance. The momentum distribution differs drastically for those obtained fo...

Bunium is one of the interested genus that grow in different region Iraq, it within family Umbelliferae (Apiaceae), and species this have a considerable fruit characteristics. The were chosen study are: B. brachyactis (Post) H. Wolff, caroides (Boiss.) Hausskn. Ex Bornm., chaerophylloides (Regel& Schmalh.) Drude, rectangulum Boiss. & Hausskn., verruculosum C.C.Towns. avromanum (Boiss.&a...

We studied two BaFe(2-x)N(I)xAs2 (Ni-doped Ba-122) single crystals at two different doping levels (underdoped and optimally doped) using an optical spectroscopic technique. The underdoped sample shows a magnetic phase transition around 80 K. We analyze the data with a Drude-Lorentz model with two Drude components (D1 and D2). It is known that the narrow D1 component originates from electron car...

The impacts of radiative, electrical and thermal losses on the performances of nanoscale-gap thermophotovoltaic (nano-TPV) power generators consisting of a gallium antimonide cell paired with a broadband tungsten and a radiatively-optimized Drude radiator are analyzed. Results reveal that surface mode mediated nano-TPV power generation with the Drude radiator outperforms the tungsten radiator, ...