Superconducting Pb island nanostructures studied by scanning tunneling microscopy and spectroscopy.
Superconductivity of nanosized Pb-island structures whose radius is 0.8 to 2.5 times their coherence length was studied under magnetic fields using low-temperature scanning tunneling microscopy and spectroscopy. Spatial profiles of superconductivity were obtained by conductance measurements at zero-bias voltage. Critical magnetic fields for vortex penetration and expulsion and for superconductivity breaking were measured for each island. The critical fields depending on the lateral size of the islands and existence of the minimum lateral size for vortex formation were observed.
Nishio
Takahiro
T
The Institute for Solid State Physics, The University of Tokyo, Kashiwa-no-ha, Kashiwa, Japan.
An
Toshu
T
Nomura
Atsushi
A
Miyachi
Kousuke
K
Eguchi
Toyoaki
T
Sakata
Hideaki
H
Lin
Shizeng
S
Hayashi
Nobuhiko
N
Nakai
Noriyuki
N
Machida
Masahiko
M
Hasegawa
Yukio
Y