| Title | Magneto-Transport Study of Pure and Co Doped ZnO Thin Films |
| Publication Type | Journal Article |
| Year of Publication | 2012 |
| Authors | Ghoshal, S, Kumar, PSA |
| Journal | IEEE Transactions on Magnetics |
| Volume | 48 |
| Pagination | 3426-3429 |
| Date Published | Nov |
| ISSN | 0018-9464 |
| Keywords | Absorption, carrier concentration, carrier density, carrier mean free path, cobalt, degenerate semiconductors, dilute magnetic semiconductor, Dilute magnetic semiconductors (DMSs), Doping, electron conduction, exchange interactions (electron), Hall mobility, II-VI semiconductors, localised spins, low-temperature magnetotransport properties, Magnetic resonance imaging, magnetic thin films, magnetoresistance, mean free path, negative resistance, negative transverse magnetoresistance, perturbation theory, pulsed laser deposition, Resistance, s-d exchange scattering, Scattering, semiconductor growth, semiconductor thin films, semimagnetic semiconductors, spin dynamics, temperature 4.5 K, temperature measurement, thin films, third-order perturbation expansion, wide band gap semiconductors, zinc compounds, Zinc oxide, ZnO, ZnO:Co |
| Abstract | A detailed low temperature magneto-transport study is carried out to understand the transport mechanism in pure and Co doped ZnO thin films grown by pulsed laser deposition (PLD) technique. A negative transverse magneto-resistance (MR) (with a value 4% at 4.5 K) which decreases monotonically with the increase in temperature, is observed for the undoped ZnO film. A competition between positive and negative MR is observed for the Co doped ZnO samples. In this case at higher field values negative MR contribution dominates over the positive MR, which gives rise to a slope change in the MR data. Our data for MR shows excellent agreement with the semi-empirical formula given by Khosla , which is originally proposed for the degenerate semiconductors. This formula incorporates the third order perturbation expansion of the s-d exchange scattering of the conduction electrons from the localised spins. We have also obtained the Hall mobility, carrier conc. and mean free path as function of temperature for the pure ZnO film. |
| DOI | 10.1109/TMAG.2012.2196031 |
