Low-lying energies for two electrons in the type-II quantum dot, as a function of the magnetic flux Φ. Solid and dash lines indicate spin-singlet and triplet, respectively. The ratio of the dot radius R to the effective Bohr radius aB = 4πϵħ2/mee2 is (a) 0.01, (b) 0.1, (c) 1, and (d) 10. The ground-state energy oscillates by the period of h/2e for R/aB ≳ 1.
Okuyama et al. Nanoscale Research Letters 2011 6:351 doi:10.1186/1556-276X-6-351