(Sn, Fe)-codoped In2O3 epitaxial films were deposited on (111)-oriented Y-stabilized ZrO2 substrates by pulsed laser deposition with constant Fe concentration and different Sn concentrations. The influence of Sn concentration on the crystal structure and properties of Fe-doped In2O3 ferromagnetic semiconductor films has been investigated systematically. Experimental results indicate that Sn dop...

0008-6223/$ see front matter 2013 Elsevi http://dx.doi.org/10.1016/j.carbon.2013.04.065 * Corresponding author: Fax: +86 025 5209060 E-mail address: [email protected] (Z.H. Ni We present systematical Raman studies of nitrogen doped graphene (NG). Defective graphene by Ar ion bombardment was also studied for comparison. It was found that the defects/nitrogen dopants in NG are not homogenous. Our r...

We investigate the effect of Rh doping in Sr2IrO4 using X-ray absorption spectroscopy (XAS). We observed appearance of new electron-addition states with increasing Rh concentration (x in Sr2Ir1-xRhxO4) in accordance with the concept of hole doping. The intensity of the hole-induced state is however weak, suggesting weakness of charge transfer (CT) effect and Mott insulating ground states. Also,...

We report a combined theoretical and experimental search for thermoelectric materials based on semiconducting zinc antimony. Influence of three new doping elements (sodium, potassium and boron) on the electronic properties was investigated as well as the carrier concentration and temperature dependence of the thermoelectric coefficients obtained through density-functional calculations and Boltz...

Serials of Mn doping by substituting Cd sites on Cu2CdSnSe4 are prepared by the melting method and the spark plasma sintering (SPS) technique to form Cu2Cd1-xMnxSnSe4. Our experimental and theoretical studies show that the moderate Mn doping by substituting Cd sites is an effective method to improve the thermoelectric performance of Cu2CdSnSe4. The electrical resistivity is decreased by about a...

Doping—the intentional introduction of impurities into a material—is fundamental to controlling the properties of bulk semiconductors. The prospect of new technologies has motivated similar efforts to dope semiconductor nanocrystals since their discovery two decades ago. Despite some successes [1–5], many of these efforts have failed, for reasons that remain mysterious. For example, individual ...

In monolayer graphene, substitutional doping during growth can be used to alter its electronic properties. We used scanning tunneling microscopy, Raman spectroscopy, x-ray spectroscopy, and first principles calculations to characterize individual nitrogen dopants in monolayer graphene grown on a copper substrate. Individual nitrogen atoms were incorporated as graphitic dopants, and a fraction o...

The relationship between charge transport, defects and ferroelectric response is established for K0.5Na0.5NbO3 (KNN) and Mn-doped KNN ceramics. At room temperature the conduction in KNN is associated with hole transport and can be suppressed by Mn doping. Because of that a less leaky ferroelectric hysteresis loop is obtained for Mn-doped KNN. At high temperatures the conduction is dominated by ...

We present a kinetic Monte Carlo (kMC) model to simulate the ionic conduction in bulk single crystal Yttria-stabilized Zirconia. An interacting energy barrier model is developed to take into account the interactions between ions by combining density functional theory calculations and the cluster expansion method. The electrical impedance as a function of doping concentration is predicted by kMC...

In molecular-beam epitaxy a monolayer of Pb on the Si~111! surface induces single-crystal growth at temperatures well below those required for similar growth on a bare surface. We demonstrate that the suppression of dopant segregation at the lower temperatures attainable by Pb-mediated growth allows the incorporation of As donors at concentrations reaching a few atomic percent. When Pb and Si a...