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Tunneling into the normal state of Pr2-xCexCuO4
Y Dagan1, M M Qazilbash, R L Greene
1Center for Superconductivity Research, Department of Physics, University of Maryland, College Park, MD 20742, USA.
Abstract:
The temperature dependence of the tunneling conductance was measured for various doping levels of Pr(2-x)CexCuO4 using planar junctions. A normal state gap is seen at all doping levels studied, x=0.11 to x=0.19. We find it to vanish above a certain temperature T*. T* is greater than T(c) for the underdoped region and it follows T(c) on the overdoped side. This behavior suggests finite pairing amplitude above T(c) on the underdoped side.
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