In this article, a scanning probe method based on nanoscale capacitance measurements was used to investigate the lateral homogeneity of the electron mean free path both in pristine and ion-irradiated graphene. The local variations in the electronic transport properties were explained taking into account the scattering of electrons by charged impurities and point defects (vacancies). Electron me...

A simple and rapid reverse-phase high-performance liquid chromatographic (HPLC) method for the simultaneous separation and determination of erlotinib and its process-related impurities in bulk drugs has been developed. Five process-related impurities of erlotinib have been separated on an Inerstsil ODS-3V (C18) column and detected at 254 nm using a photo diode array (PDA). This HPLC method was ...

We present a comprehensive first-principles investigation of arsenic incorporation in GaN. Incorporation of As on the N site, which has previously been implicitly assumed, is favorable only under n-type conditions in a Ga-rich environment. Less Ga-rich conditions, and particularly p-type doping, strongly favor incorporation of As on the Ga site, where it behaves as a deep double donor. Arsenic ...

A simple model is presented for the calculation of the quenched average over impurities which are rendered static by setting their mass equal to infinity. The path integral formalism of the second quantized theory contains annealed averages only. The similarity with the Gaussian quenched potential model is discussed.

Since transition metal impurities affect the electronic and optical properties of semiconductors [1], it is important to understand the role of such unavoidable impurities on those properties. At the same time, transition metals in semiconductors can be used in other unusual situations. The energy levels related to transition metal impurities are aligned with respect to each other for the same ...

We demonstrate that a giant spin Hall effect (SHE) can be induced by introducing a small amount of Bi impurities in Cu. Our analysis, based on a new three-dimensional finite element treatment of spin transport, shows that the sign of the SHE induced by the Bi impurities is negative and its spin Hall (SH) angle amounts to -0.24. Such a negative large SH angle in CuBi alloys can be explained by a...