Normal incidence intersubband absorption in vertical quantum wells

Abstract

N-doped vertical AlGaAs quantum wells have been fabricated by metalorganic vapor phase epitaxial growth of a single-doped AlGaAs layer on a submicron grating. Intersubband absorption at normal incidence is demonstrated in those quantum wells. This opens new possibilities for infrared quantum well devices using intersubband transitions.

Exciton diffusion dynamics in quantum nanostructures on V-groove patterned substrates

“…In the case of the AlGaAs on V-groove patterned GaAs substrates by metalorganic vapour phase epitaxy (MOVPE), Ga-rich AlGaAs with lateral dimension of a few hundred angstrom is spontaneously formed and this acts as a QW vertical to the substrate. The QW, referred to as a spontaneous vertical quantum well (SVQW), has some unique properties which cannot be obtained with conventional QWs including the sensitivity of the intersubband absorption for the normal incident lights [9]. These methods are successful at obtaining quantum nanostructures, however, there are problems to be taken into account.…”

Time-resolved photoluminescence study on AlxGa1−xAs spontaneous vertical quantum well structures

“…Recently, Berger et al demonstrated normal incident intersubband transitions by using n-type AlGaAs SVQW grown by MOVPE. 7 In addition, exploitation of SVQW as barrier layers for GaAs QWRs on V-grooved substrates was found to greatly affect their optical properties due to the nonuniformity of the alloy composition. Wang et al reported on the change of photoluminescence ͑PL͒ spectra of AlGaAs/GaAs QWRs on V-grooved GaAs substrates by selective removal of the AlGaAs barrier layer, and demonstrated the carrier capture efficiency of QWRs are greatly modified.…”

Electronic States of a Shallow Hydrogenic Donor Impurity in Different Shaped Semiconductor Quantum Wells

“…Parabolic structures are well known in designing infrared detectors with low leak currents and low electricfield sensitivity. [6,7] VQWs have some unique properties, which cannot be obtained with conventional QWs, including the sensitivity of the intersubband absorption for the normal incident lights. [8] Furthermore, VQWs have potential applications in novel semiconductor diode laser [9] as well as in infrared optoelectronics based on intersubband QW transitions.…”