Environment-assisted tunneling as an origin of the Dynes density of states.
We show that the effect of a high-temperature environment in current transport through a normal metal-insulator-superconductor tunnel junction can be described by an effective density of states in the superconductor. In the limit of a resistive low-Ohmic environment, this density of states reduces into the well-known Dynes form. Our theoretical result is supported by experiments in engineered environments. We apply our findings to improve the performance of a single-electron turnstile, a potential candidate for a metrological current source.
Pekola
J P
JP
Low Temperature Laboratory, Aalto University, P.O. Box 13500, FI-00076 Aalto, Finland.
Maisi
V F
VF
Kafanov
S
S
Chekurov
N
N
Kemppinen
A
A
Pashkin
Yu A
YA
Saira
O-P
OP
Möttönen
M
M
Tsai
J S
JS