Extracting the diffusivity ratio from point contact Andreev reflection spectroscopy and upper critical field measurements in MgB2

Yates, Karen A. and Miyoshi, Y. and Grunwell, J. and Riggall, K. and Bugoslavsky, Y. and Chen, Soo Kien and MacManus Driscoll, Judith L. and Pogrebnyakov, A. V. and Xi, X. X. and Cohen, L. F. (2008) Extracting the diffusivity ratio from point contact Andreev reflection spectroscopy and upper critical field measurements in MgB2. Journal of Physics: Conference Series, 97 (1). 012213. ISSN 1742-6588

Full text not available from this repository.

Official URL: http://dx.doi.org/10.1088/1742-6596/97/1/012213

Abstract

The di®usivity ratio ´, which measures the relative intraband scattering in the ¼ and ¾ bands in MgB2 has been determined by ¯tting the Hc2(T) at T » Tc and by Point Contact Andreev Re°ection. We ¯nd a satisfactory agreement between the values for ´ obtained by both methods for c-axis orientated MgB2 thin ¯lms. Point contact Andreev Re°ection was then applied to bulk MgB2 containing Mg vacancies. Spectra obtained in zero ¯eld indicate a distribution of the two gaps ¢¾;¼ but no merging of the values with increased magnesium de¯ciency. Spectra ¯tted as a function of ¯eld are consistent with an increase in ¼ intraband scattering with increasing magnesium de¯ciency. Measurement of the point contact Andreev re°ection spectra as a function of temperature revealed features not immediately expected from current theoretical models.

Item Type:Article
Faculty or Institute:Faculty of Science
Publisher:Institute of Physics
DOI Number:10.1088/1742-6596/97/1/012213
Altmetrics:http://www.altmetric.com/details.php?domain=psasir.upm.edu.my&doi=10.1088/1742-6596/97/1/012213
ID Code:6699
Deposited By: Najwani Amir Sariffudin
Deposited On:20 May 2010 02:05
Last Modified:28 Jul 2010 01:37

Repository Staff Only: Edit item detail


Universiti Putra Malaysia Institutional Repository

Universiti Putra Malaysia Institutional Repository is an on-line digital archive that serves as a central collection and storage of scientific information and research at the Universiti Putra Malaysia.

Currently, the collections deposited in the IR consists of Master and PhD theses, Master and PhD Project Report, Journal Articles, Journal Bulletins, Conference Papers, UPM News, Newspaper Cuttings, Patents and Inaugural Lectures.

As the policy of the university does not permit users to view thesis in full text, access is only given to the first 24 pages only.