量子点的合成和应用Quantum Dots Science and Applications.pptVIP

* * * * * * Quantum Dots Science and Applications Jiameng Cui, Jie Zhang, Dejuan Sun, Liuyang Zhu, Manman Qian, Qiang Huang, Lei Zhang, Haifeng Zhang, Qiudi Yue. 12, 2015 Qiudi Yue. Content What are Quantum Dots? Quantum dots are semi-conductors that are on the nanometer scale. Obey quantum mechanical principle of quantum confinement. Exhibit energy band gap that determines required wavelength of radiation absorption and emission spectra. Requisite absorption and resultant emission wavelengths dependent on dot size. Fig. 1. Schematic plot of the single particle energy band gap. The upper parabolic band is the conduction band, the lower the valence. Quantum Confinement Materials. 2010, 3, 2260-2345. Size-dependent quantum confinement effects develop when the thickness of an electronic layer approaches the de Broglie wavelength of the electron in a quantum well structure, and when the radius of a semiconductor sphere is smaller than the bulk-exciton Bohr radius, in a nanocrystal Quantum Confinement Theory effective mass approximation effective mass with Coulomb interaction size-dependent capacitance. effective mass approximation based on quantum confinement classical physics based on the dielectric properties of spheres J. Chem. Edu. 2005, 82, 11. Quantum Confinement Louis E. Brus Columbia Unv. Dep. of Chemistry Moungi G Bawendi MIT Dep. of Chemistry Paul Alivisatos Lawrence Berkeley National Laboratory Xiaogang Peng Zhejiang University Dep. of Chemistry? Liberato Manna Istituto Italiano di Tecnologia Quantum Dot Celebrities Electron beam lithography Ion beam etching 2. Bottom-Up Approaches Sol-Gel process Microemulsion Process Hot-Solution Decomposition Process Other Synthesis Processes Synthesis Approaches 1. Top-Down Synthesis Processes Electron beam lithography Synthesis Approaches 1. Top-Down Synthesis /articles/Lithography.html Ion beam etching Synthesis Approaches 1. Top-Down Synthesis /articles/Lithography.html Electron beam lithography