dc.contributor.author | Roshchin, I. V. | eng |
dc.contributor.author | Abeyta, A. C. | eng |
dc.contributor.author | Greene, L. H. | eng |
dc.contributor.author | Tanzer, T. A. | eng |
dc.contributor.author | Dorsten, J. F. | eng |
dc.contributor.author | Bohn, P. W. | eng |
dc.contributor.author | Han, Sang-Wook, 1964- | eng |
dc.contributor.author | Miceli, Paul F. | eng |
dc.contributor.author | Klem, J. F. | eng |
dc.date.issued | 2002 | eng |
dc.description | URL:http://link.aps.org/doi/10.1103/PhysRevB.66.134530
DOI:10.1103/PhysRevB.66.134530 | eng |
dc.description.abstract | High-quality thin Nb and NbN films (60-100 Å) are grown on (100) n+-InAs (n=1019cm-3) substrates by dc-magnetron sputter deposition. Studies of the electronic properties of interfaces between the superconductor and the semiconductor are done by Raman scattering measurements. The superconducting proximity effect at superconductor-semiconductor interfaces is observed through its impact on inelastic light scattering intensities originating from the near-interface region of InAs. The InAs longitudinal optical phonon LO mode (237cm-1) and the plasmon-phonon coupled modes L- (221cm-1) and L+ (1100 to 1350cm-1), for n+=1×1019-2×1019cm-3 are measured. The intensity ratio of the LO mode (associated with the near-surface charge accumulation region, in InAs) to that of the L- mode (associated with bulk InAs), is observed to increase by up to 40% below the superconducting transition temperature. This temperature-dependent change in light scattering properties is only observed with high quality superconducting films and when the superconductor and the semiconductor are in good electrical contact. A few possible mechanisms of the observed effect are proposed. | eng |
dc.description.sponsorship | We gratefully acknowledge support from the United States Department of Energy through Materials Research Laboratory~Grant No. DEFG02-96ER45439! ~I.V.R., A.C.A., L.H.G.,
T.A.T., J.F.D., P.W.B., J.F.K.!, and from the United States Department of Energy through Midwest Superconductivity
Consortium ~MISCON! ~Grant No. DE FG02-90ER45427! and the NSF ~Grant No. DMR 96-23827! ~S.W.H., P.F.M.!. SEM, XRD, XPS, and RBS materials characterizations were
performed at the Center for Microanalysis of Materials and Microfabrication Center at Frederick Seitz Materials Research
Laboratory, University of Illinois at Urbana-
Champaign ~Grant No. DE FG02-96ER45439!. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin company, for the United States Department
of Energy under Contract No. DE-AC04-94AL85000. | eng |
dc.identifier.citation | Phys. Rev. B 66, 134530 (2002) | eng |
dc.identifier.issn | 1098-0121 | eng |
dc.identifier.uri | http://hdl.handle.net/10355/7461 | eng |
dc.language | English | eng |
dc.publisher | American Physical Society | eng |
dc.relation.ispartofcollection | University of Missouri--Columbia. College of Arts and Sciences. Department of Physics and Astronomy. Physics and Astronomy publications | eng |
dc.subject | tunneling phenomena | eng |
dc.subject | point contacts | eng |
dc.subject | weak links | eng |
dc.subject | Josephson effects | eng |
dc.subject | electron states at surfaces and interfaces | eng |
dc.subject.lcsh | Lattice dynamics | eng |
dc.subject.lcsh | Tunneling (Physics) | eng |
dc.subject.lcsh | Surfaces (Physics) | eng |
dc.subject.lcsh | Interfaces (Physical sciences) | eng |
dc.title | Observation of the superconducting proximity effect in Nb/InAs and NbNx/InAs by Raman scattering | eng |
dc.type | Article | eng |