Quantum size effects on the perpendicular upper critical field in ultrathin lead films.

Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
Physical Review Letters (Impact Factor: 7.73). 01/2006; 95(24):247005. DOI: 10.1103/PhysRevLett.95.247005
Source: PubMed

ABSTRACT We report the thickness-dependent (in terms of atomic layers) oscillation behavior of the perpendicular upper critical field Hc2perpendicular in the ultrathin lead films at the reduced temperature (t = T/Tc). Distinct oscillations of the normal-state resistivity as a function of film thickness have also been observed. Compared with the Tc oscillation, the Hc2perpendicular shows a considerable large oscillation amplitude and a pi phase shift. The oscillatory mean free path caused by the quantum size effect plays a role in Hc2perpendicular oscillation.

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