2011/12/17 by Rajib Rahman, Erik Nielsen, Richard P. Muller +1
Engineering · Physics and Astronomy · #Atomic physics #Charge (physics) #Condensed matter physics #Electron #Optoelectronics #Physics #Quantum and electron transport phenomena #Quantum dot #Quantum mechanics #Semiconductor #Semiconductor Quantum Structures and Devices #Semiconductor materials and devices #Silicon #cond-mat.mes-hall #cond-mat.mtrl-sci #quant-ph
paper · pdf · doi:10.1103/physrevb.85.125423
published as Physical Review B 85, 125423 (2012) · 5 pages, 3 figures
arxiv created 2011/12/17 · openalex publication_date 2012/03/20 · arxiv updated 2012/03/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Quantum dots are artificial atoms used for a multitude of purposes. Charge defects are commonly present and can significantly perturb the designed energy spectrum and purpose of the dots. Voltage controlled exchange energy in silicon double quantum dots (DQDs) represents a system that is very sensitive to charge position and is of interest for quantum computing. We calculate the energy spectrum of the silicon double quantum dot system using a full configuration interaction that uses tight-binding single-particle wave functions. This approach allows us to analyze atomic scale charge perturbations of the DQD while accounting for the details of the complex momentum space physics of silicon (i.e., valley and valley-orbit physics). We analyze how the energy levels and exchange curves for a DQD are affected by nearby charge defects at various positions relative to the dot, which are consistent with defects expected in the metal-oxide-semiconductor system.