Excitons in InP quantum wires with dielectric barriers

Spectra of linear absorption and photoluminescence (PL) at different polarization of the laser excitation; photoluminescence excitation (PLE) spectra and time - resolved PL of the InP quantum wires (QWRs) crystallized in transparent nanotubes of chrysotile asbestos have been measured. We evaluate the exciton ground state binding energy as large as 200 meV. In the presence of the strong resonant laser pumping of InP QWRs (the energy of laser photon coincides with the absorption band of QWRs) the induced suppression and enhancement of PL in different parts of the spectra and the blue shift (about 13meV) of the PL maximum relatively to the energy of laser photon have been observed. The PL features of InP QWRs has been explained by saturation of the capture centers and Auger process

Excitons in InP quantum wires with dielectric barriers

Spectra of linear absorption and photoluminescence (PL) at different polarization of the laser excitation; photoluminescence excitation (PLE) spectra and time - resolved PL of the InP quantum wires (QWRs) crystallized in transparent nanotubes of chrysotile asbestos have been measured. We evaluate the exciton ground state binding energy as large as 200 meV. In the presence of the strong resonant laser pumping of InP QWRs (the energy of laser photon coincides with the absorption band of QWRs) the induced suppression and enhancement of PL in different parts of the spectra and the blue shift (about 13meV) of the PL maximum relatively to the energy of laser photon have been observed. The PL features of InP QWRs has been explained by saturation of the capture centers and Auger process

Optical properties of excitons in semiconductor (InP)-insulator quantum wires

Features in the spectra of absorption, luminescence, and luminescence efficiency obtained under sample excitation with differently polarized laser radiation, and the nonlinear dependence of the luminescence intensity on the excitation level are explained as due to excitonic transitions in semiconductor (InP)-insulator (chrysotile asbestos) quantum wires. The measured excitonic-transition energies in the quantum wires are in quantitative agreement with calculations. The calculations took into account both the size quantization in a quasi-one-dimensional structure and the “dielectric enhancement” of excitons (the noticeable increase of the exciton binding energy and of the excitonic-transition oscillator strength associated with the increased attraction between the electron and the hole due to the large difference between the dielectric permittivities of the semiconductor and the dielectric matrix)

Linear and nonlinear optical properties of excitons in semiconductor-dielectric quantum wires

The characteristic features of the absorption, luminescence and photoluminescence excitation spectra of InP nanocrystals crystallized in chrysotile asbestos nanotubes and CdS nanocrystals crystallized in hollow channels of a dielectric template have been explained in terms of exciton transitions in semiconductor–dielectric quantum wires. In these structures, the dielectric confinement effect leads to a considerable increase of the exciton binding energy—the Coulomb attraction between electron and hole is considerably enhanced as a result of the difference between the permittivities of the semiconductor and insulator. The kinetics of porous InP photoluminescence at high excitation by picosecond laser pulses has been explained by the slowing down of the intraband energy relaxation, collective exciton–exciton (electron) interaction and Auger recombination in nanostructures