Electrodynamic dip in the local density of states of a metallic wire.
We have measured the differential conductance of a tunnel junction between a thin metallic wire and a thick ground plane, as a function of the applied voltage. We find that near zero voltage, the differential conductance exhibits a dip, which scales as 1/square root of [V] down to voltages V approximately 10k(B)T/e. The precise voltage and temperature dependence of the differential conductance is accounted for by the effect on the tunneling density of states of the macroscopic electrodynamics contribution to electron-electron interaction, and not by the short-ranged screened-Coulomb repulsion at microscopic scales.
Pierre
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F
Service de Physique de l'Etat Condensé, Commissariat à l'Energie Atomique, Saclay, 91191 Gif-sur-Yvette, France.
Pothier
H
H
Joyez
P
P
Birge
N O
NO
Esteve
D
D
Devoret
M H
MH