Competition between leak and quantized currents leads to the breakdown of the current quantization as the frequency f of RF signal is smaller than the tunneling rate Γleak We find that when f > Γleak, the dc current is quantized, while the much larger current than quantized current flows through the dot when f < Γleak. We also find new fine structures in the current plateaus resulting from the quantized level spacing ΔE. These structures are washed out at the temperature kBT ~ ΔE, though the quantized plateaus remain. The quantized plateaus are washed out at kBT ~ e2/C, where C is the capacitance of the dot.
ASJC Scopus subject areas
- Physics and Astronomy(all)