We are modeling the InAs double QDs and QRs, embedded into the GaAs substrate. For the numerical modeling we apply an effective approach] in which the combined effect of strain, piezoelectricity and interband interactions are simulated by an effective potential. Tunneling in the double quantum dot (ring) is studied by influence of inter-dot distance and QD geometry. The cases of identical and non-identical QDs in DQD are considered. For identical QDs the tunneling goes consecutively from high energy levels to the ground state. Character of the tunneling is changed essentially when the QDs of the system are non-identical. In particular, we show that violation of symmetry of the DQD geometry makes a trouble for the tunneling. For DQRs we found that the electron states with the same type of rotation symmetry play important role for the dynamical tunneling. Chaotic double quantum systems are also considered to find the chaos assistance for tunneling. This work is supported by NSF CREST award; HRD-0833184 and NASA award NNX09AV07A.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2012: Electronics, Devices, Fabrication, MEMS, Fluidics and Computational (Volume 2)
Published: June 18, 2012
Pages: 56 - 59
Industry sectors: Advanced Materials & Manufacturing | Sensors, MEMS, Electronics
Topicss: Nanoelectronics, Photonic Materials & Devices