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The energy of the indirect X exciton in AlxGa1-xAs epitaxial layers (with 0.38 < x < 0.81) has been determined by photoluminescence measurements at a sample temperature of 12 K; from these data, the dependence on the Al concentration x of the energy of the ...
We studied the influence of the indium composition y, growth temperature T(s) and InGaAs quantum-well channel thickness d(ch) on the 300 and 77 K Hall electrical properties of pseudomorphic modulation doped field effect transistor (MODFET)-type heterostruc ...
We report on the first observation of both confined optical phonons and interface phonons in a single strained InAs quantum well grown on InP. Quasi resonant Raman measurements allow for the observation of interface modes. Informations about the mismatch i ...
We discuss the growth of lattice matched GaInAs, GaInAsP and GaInAsP/GaInAs multiple quantum well structures for high speed laser applications. Optical cavities, including five 90 angstrom GaInAs quantum wells with GaInAsP barriers and waveguides showed a ...
Recently Zachau, Kash, and Masselink [Phys. Rev. B 44, 4048 (1991)] determined hole-subband dispersions in quantum wells experimentally with the use of hot-electron-acceptor luminescence. We present here results of multiple-band calculations, which are in ...
In this work the interface between transition metals (Fe, Co) and Si has been investigated by soft X-ray photoemission spectroscopy. Synchrotron radiation has been used as photon source, measuring valence bands, Si2p and metal 3p core levels with high surf ...
GaAs/AlxGa1-xAs multiple-quantum-well structures with identical well thicknesses (almost-equal-to 119 angstrom) but with different Al contents x in the barrier (x almost-equal-to 0. 1, 0.2, 0.45, and 1) were grown by molecular-beam epitaxy. We report the c ...
We report on the first observation of both confined optical phonons and interface phonons in a single strained InAs quantum well grown on InP. Quasi resonant Raman measurements allow for the observation of interface modes. Informations about the mismatch i ...
We applied the internal photoemission technique to the direct observation of deep levels together with barrier heights and band discontinuities at different semiconductor heterostructure interfaces. Its performances and capabilities are superior to those o ...
A steady state photoluminescence experiment is reported investigating the lifetime of an electron-hole plasma confined in a quintum well. The results are compared with theoretical evaluations of the pure radiative decay rate and good agreement is found. Th ...