Quantum Size Effects on the Perpendicular Upper Critical Field in Ultrathin Lead Films

Department of Physics, Oklahoma State University - Stillwater, SWO, Oklahoma, United States
Physical Review Letters (Impact Factor: 7.51). 01/2006; 95(24):247005. DOI: 10.1103/PhysRevLett.95.247005
Source: PubMed


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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