We investigate the effect of quantum flucuations on the Coulomb blockade in a single tunnel junction coupled to its environment by a transmission line of arbitrary impedance Z (ω). The quantized oscillating modes of the transmission line are suddenly displaced when an electron tunnels through the junction. For small Z (relative to the quantum of resistance), a weak power-law sero-bias anomaly occurs associted with the infrared-divergent shakeup of low-frequency transmission-line modes. For large Z, the full blockade is recovered. Comparison with recent experiments is made.
Citation: Physical Review Letters
Pub Type: Journals