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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Charge dynamics of 2H- TaSe2 along the less-conducting c-axis
B Ruzicka1, L Degiorgi, H Berger
1Laboratorium für Festkörperphysik ETH Zurich, CH-8093 Zurich, Switzerland.
Abstract:
We present an optical study of 2H-TaSe2 along the less conducting c-axis. This dichalcogenide compound belongs to a large class of conductors called "bad metals" (with a mean free path smaller than the lattice constant along the c-axis), which also includes the superconducting cuprates. The optical response shows the progressive development of a pseudogaplike feature with decreasing temperature. The spectral weight lost by the opening of such a pseudogap goes into the narrow Drude component, developing at low frequency and temperature. There is no violation of the sum rule in 2H-TaSe2 contrary to the cuprates.
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