NOR gate response in a double quantum ring: An exact result

作者：Maiti Santanu K^*

来源：Solid State Communications, 2009, 149(47-48): 2146-2150.

DOI：10.1016/j.ssc.2009.09.025

• Double quantum ring
• Conductance
• I-V characteristic
• NOR gate

NOR gate response in a double quantum ring, where each ring is threaded by a magnetic flux phi, is investigated. The double quantum ring is sandwiched symmetrically between two semi-infinite one-dimensional metallic electrodes, and two gate voltages, namely, V-a and V-b, are applied, respectively, in lower arms of the two rings those are treated as the two inputs of the NOR gate. A simple tight-binding model is used to describe the system, and all the calculations are done through the Green's function formalism. Here we calculate exactly the conductance-energy and current-voltage characteristics as functions of the ring-to-electrode coupling strengths, magnetic flux and gate voltages. Our numerical study predicts that, for a typical value of the magnetic flux phi = phi(0)/2 (phi(0) = ch/e, the elementary flux-quantum), a high output current (1) (in the logical sense) appears if both the inputs to the gate are low (0), while if one or both are high (1), a low output current (0) results. It clearly demonstrates the NOR gate behavior, and this aspect may be utilized in designing an electronic logic gate.

• 出版日期2009-12