J Appl

Phys 2009, 105:113516.CrossRef 22. Hsieh Y-P, Chen H-Y, Lin M-Z, Shiu S-C, Hoffmann M, Chern M-Y, Jia X, Yang Y-J, Chang H-J, Huang H-M, Tseng S-C, Chen L-C, Chen K-H, Lin C-F, Liang C-T, Chen YF: Electroluminescence from ZnO/Si-nanotips light-emitting diodes. Nano Lett 1839, 2009:9. 23. Lin S-K, Wu KT, Huang CP, Liang C-T, Chang YH, Chen YF, Chang PH, Chen NC, Chang C-A, Peng HC, Shih CF, Liu KS, Lin TY: Electron selleck chemicals llc transport in In-rich In x Ga 1-x N films. J Appl Phys 2005, Luminespib research buy 97:046101.CrossRef 24. Chen JH, Lin JY, Tsai JK, Park H, Kim G-H, Youn D, Cho HI, Lee EJ, Lee JH, Liang C-T, Chen YF: Experimental evidence for Drude-Boltzmann-like transport in a two-dimensional electron gas in an AlGaN/GaN heterostructure. J Korean Phys Soc 2006, 48:1539. Competing interests The authors declare that they have no competing interests. Authors’ contributions WJC, JKW, and JCL performed the experiments. WJC and JKW fabricated the devices. MFS and YHC coordinated the project. STL and DRH provided key interpretation of the data. WJC, HDL, DRH, and CTL drafted the paper. All authors read and approved the final manuscript.”
“Background Investigation of new physical properties of zero-dimensional objects, particularly semiconductor Combretastatin A4 supplier quantum dots, is a fundamental

part of modern physics. Extraordinary properties of nanostructures are mainly a consequence of quantum confinement effects. A lot of theoretical

and experimental works are devoted to the study of the electronic, impurity, excitonic, and optical properties of semiconductor QDs. Potential applications of various nanostructures in optoelectronic and photonic devices are predicted and are under intensive study of many research groups [1–7]. In low-dimensional structures along with size quantization (SQ) effects, one often deals with the Coulomb interaction between charge carriers (CC). SQ can successfully compete with Coulomb quantization and even prevails over it in certain cases. In Coulomb problems in the SQ systems, one has to use different quantum mechanical approaches along with numerical methods. Thus, the significant difference between the effective masses of the impurity (holes) Selleckchem C59 and electron allows us to use the Born-Oppenheimer approximation [8, 9]. When the energy conditioned by the SQ is much more than the Coulomb energy, the problem is solved in the framework of perturbation theory, where the role of a small correction plays the term of the Coulomb interaction in the problem Hamiltonian [10]. The situation is radically changed when the effective mass of the impurity center (hole) is comparable to the mass of the electron. For example, in the narrow-gap semiconductors for which the CC standard (parabolic) dispersion law is violated, the effective masses of the electron and light hole are equal [11–14].