Figure 13

nextnano simulation of transmission for the tunnel-coupled wire (TCW: panels (a-c)) and the TCW – Aharonov–Bohm interferometer – TCW nanodevice (TCW–AB–TCW: panels (d-f)). Both devices are connected to four terminals (external leads marked by white numbers). Panels (a,d): Potential landscapes of TCW and TCW–AB–TCW devices. Red and light blue separation regions denote impenetrable (very high with the height \(V_{\infty }= 10\mathrm{{~eV}}\)) and penetrable (tunneling with the height \(V_{\mathrm{{T}}} \)) potential barriers, respectively. Green regions mark those parts of the device where the gate voltages \(0.5\mathrm{{~eV} }\) and \(V_{\mathrm{{g}}} \) are applied. Panels (b,e): Energy-dependent transmission of the electron from the lead no. 1 into the leads no. 3 (\(T_{13}\)) and no. 4 (\(T_{14}\)). Red dashed lines mark some electron energies where the reflection is almost absent, \(T_{13} + T_{14} \simeq 1 \) (\(E = 9.2\text{ meV}\) for TCW and 7.5 meV for TCW–AB–TCW). Panels (c,f): Almost reflectionless transmission of the electron with fixed energy as a function of \(V_{\mathrm{{T}}} \) (TCW) and \(V_{\mathrm{{g}}} \) (TCW–AB–TCW). Dots in panel (c) correspond to the semi-phenomenological theory supplied by the 1D simulation of the spectrum at the center of the device, \(x = 0 \) (marked by the dashed line in panel (a)). Insets: The same dependence as in the main figures but for devices with half length, where the accessible number of quantum oscillations is much smaller