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We investigated the magneto-optical properties of the Pöschl–Teller GaAs/AlAs quantum well (QW) due to the electron–interface optical (IO) phonon interaction based on the optically-detected (OD) magneto–IO-phonon resonance (MIOPR) effect. The methods of the operator projection and the profile were used to calculate the MO-absorption power (MOAP) and measure the full width at half maximum (FWHM) of the OD-MIOPR peaks. The results are as follows: The well-width (L W), the temperature of the electron–phonon system (T), and the magnetic field (B) strongly affect the MOAP and the FWHM of the OD-MIOPR peaks for both the two emission and absorption cases of IO-phonons in both the materials of the well and the barrier. The FWHMs in both the materials of the well and the barrier for the absorption case of an IO-phonon are bigger than those for the emission case. The FWHM due to IO-phonon interaction in the GaAs material of the well is stronger than that in the AlAs material of the barrier for both the two IO-phonons emission and absorption cases. Especially, the result also showed that the FWHMs in the Pöschl–Teller QW are always bigger than those in the rectangular QW for the two emission and absorption cases of IO-phonons in both the GaAs and AlAs materials of the well and the barrier, respectively. Our specific results are expected to be promising data for potential applications in optoelectronic devices. • Electron–interface-phonon interaction strength in Pöschl–Teller QW is studied. • Emission and absorption of interface phonons in GaAs and AlAs are calculated and compared. • Results of these calculations are compared with those in rectangular QW. • Contribution of phonon absorption (emission) in GaAs (AlAs) is the largest (smallest). • Electron–interface-phonon interaction strength is enhanced in Pöschl–Teller QW. [ABSTRACT FROM AUTHOR]

We investigate the influence of phonon confinement on the optically detected magneto-phonon resonance (ODMPR) effect and ODMPR line-width in quantum wells. The ODMPR conditions as functions of the well's width and the photon energy are also obtained. The shifts of ODMPR peaks caused by the confined phonon are discussed. The numerical result for the GaAs/AlAs quantum well shows that in the two cases of confined and bulk phonons, the line-width (LW) decreases with increasing well's width and increases with increasing temperature. Furthermore, in the small range of the well's width, the influence of phonon confinement plays an important role and cannot be neglected in reaching the ODMPR line-width. [ABSTRACT FROM AUTHOR]

In this work, the combined effect of aluminum concentration, hydrostatic pressure, temperature, and confinement frequency of a parabolic quantum well (PQW) on the phonon-assisted cyclotron resonance (PACR) via two-photon absorption process under applied electric field is investigated theoretically. The analytical expression of the magneto-optical absorption coefficient (MOAC) is obtained by relating it to the transition probability for the absorption of photons. The numerical results are calculated for typical GaAs/GaAlAs quantum well. The obtained results show that the hydrostatic pressure, aluminum concentration, temperature, and confinement frequency have a significant effect on the MOAC as well as on the half-width. Moreover, it has been found that the optical properties of the GaAs/GaAlAs PQW can be modified by changing these parameters. This gives a new capacity for optical device applications. [ABSTRACT FROM AUTHOR]

The multi-photon (nonlinear) optical absorption power by electrons in square quantum wells, taking account the electron-confined optical phonon interaction, is calculated using the state-dependent projection technique. We numerically obtain the dependence of the absorption power on the photon energy in the GaAs/AlAs semiconductor quantum well. By analysing this dependence, we show clearly the transition corresponding to each resonant peak, including the optically detected electrophonon resonance (ODEPR). Also, using a computational method, we obtain the line-width of the ODEPR as profiles of the curves. The dependence of the ODEPR line-width on the width of the quantum well shows that the ODEPR line-width for two-photon absorption is about one order of value smaller than it is for one-photon absorption. [ABSTRACT FROM AUTHOR]

Highlights: [•] The PACR is investigated for different mechanisms of phonon scattering. [•] The PACR is investigated via multiphoton absorption process. [•] PACR-linewidth as profiles of the curves is determined. [•] PACR-linewidth increase with temperature and magnetic field. [•] The two-photon process is about 26.3% of that in the one-photon process. [ABSTRACT FROM AUTHOR]

We theoretically study the nonlinear optical absorption phenomenon in a GaAs/GaAlAs parabolic quantum well via investigating the phonon-assisted cyclotron resonance (PACR) effect. We find that the two-photon absorption process (nonlinear) is comparable with the one-photon process (linear), and cannot be neglected in studying PACR effect. The additional peaks in the absorption spectrum due to transitions between Landau levels and electric subband energy accompanied by emission and absorption of LO-phonon are indicated. PACR behavior is strongly affected by the magnetic field, the temperature and the confinement frequency. The present work obtains an usefully resonant condition which is more general than and includes the previous resonant behaviors. [ABSTRACT FROM AUTHOR]

Abstract: Phonon-assisted cyclotron resonance (PACR) in GaAs quantum well (QW) structure is investigated via multi-photon absorption process when electrons interact with the confined acoustic phonon through deformation potential. The additional peaks in the absorption spectrum due to transitions between Landau levels accompanied with the emission and absorption of phonons are indicated. The dependence of absorption power on the temperature, magnetic field and well width is presented. Using profile method, we obtain PACR-linewidth as profiles of the curves. The temperature, magnetic field and well width dependences of the PACR-linewidth are investigated. The results are compared with those in the case of mono-photon absorption process, as well as in the electron-bulk acoustic phonon interaction. The results show that the multi-photon absorption process is strong enough to be detected in PACR. [Copyright &y& Elsevier]

In this article, using the operator projection technique, we will theoretically study the electron-interface phonon scattering process due to the absorbtion and emission of interface phonons by calculating the expression for the absorption power (AP) in GaAs/AlAs quantum wells (QWs). The full width at half maximum (FWHM) of the magneto-interface phonon resonance peaks was obtained by using the profile method. The FWHM is given as functions of the temperature, well width, and magnetic field presented to compare for both the barrier material AlAs and well material GaAs in the two cases of emission and absorbtion of interface modes. The result clearly demonstrates important roles of the interface optical modes when the well width is small enough. • Electron-interface optical phonon scattering in GaAs/AlAs QWs is investigated. • Blueshift and redshift behaviors of peaks with magnetic field and well width are discussed. • Absorption power and FWHM are affected by well width, and magnetic field. • Interface mode absorption/emission in both the well and barrier materials are compared. [ABSTRACT FROM AUTHOR]