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By Matjaž Humar.

Seminar for Theory of Nanomaterials.

Online text: humarlab.ijs.si/documents/ExcitonsinSemiconductorQuantumDots.pdf

Cited passages: Humar, §3, printed p. 6: small-radius Frenkel contrast; Humar, §3, printed pp. 5–6, equations (13)–(26); Matjaž Humar, Excitons in Semiconductor Quantum Dots, §3, printed pp. 4–6: bound pairs, effective masses and localized contrast.

Matjaž Humar explained how quantum confinement changes the optical properties of semiconductor quantum dots. Confinement raises electronic energy scales and modifies exciton states, so changing a dot's size can shift its absorption and fluorescence spectra. His treatment distinguishes regimes by comparing the dot size with the exciton's internal size and the wavelength of its motion. This prevents a bulk bound-pair model from being applied unchanged to a much smaller nanocrystal.^[ref]