Xh. Wang et Ka. Chao, CHARGING ULTRASMALL TUNNEL-JUNCTIONS IN AN ELECTROMAGNETIC ENVIRONMENT, Physical review. B, Condensed matter, 56(19), 1997, pp. 12404-12410
We have investigated the quantum admittance of an ultrasmall tunnel ju
nction with arbitrary tunneling strength under an electromagnetic envi
ronment. Using the functional-integral approach a close analytical exp
ression of the quantum admittance is derived for a general electromagn
etic environment. We then consider a specific controllable environment
where a resistance is connected in series with the tunneling junction
, for which we derived the de quantum conductance from the zero-freque
ncy limit of the imaginary part of the quantum admittance. For such an
electromagnetic environment the de conductance has been investigated
in recent experiments, and our numerical results agree quantitatively
very well with the measurements. Our complete numerical results for th
e entire range of junction conductance and electromagnetic environment
al conductance confirmed the few existing theoretical conclusions.