TY  - JOUR
A1  - Dyksik, M.
A1  - Motyka, M.
A1  - Kurka, M.
A1  - Ryczo, K.
A1  - Dallner, M.
A1  - Höfling, S.
A1  - Kamp, M.
A1  - Sęk, G.
A1  - Misiwicz, J.
T1  - Photoluminescence quenching mechanisms in type IIInAs/GaInSb QWs on InAs substrates
JF  - Optical and Quantum Electronics
N2  - Optical properties of AlSb/InAs/GaInSb/InAs/AlSb quantum wells (QWs) grown on an InAs substrate were investigated from the point of view of room temperature emission in the mid- and long-wavelength infrared ranges. By means of two independent techniques of optical spectroscopy, photoreflectance and temperature-dependent photoluminescence, it was proven that the main process limiting the performance of such InAs substrate-based type II structures is related to the escape of carriers from the hole ground state of the QW. Two nonradiative recombination channels were identified. The main process was attributed to holes tunneling to the valence band of the GaAsSb spacing layer and the second one with trapping of holes by native defects located in the same layer.
KW  - Interband cascade lasers
KW  - Quantum wells
KW  - MU-M
KW  - Fourier-transform spectroscopy
KW  - Mid-infrared photoluminescence
KW  - Type II quantum wells
KW  - Localized states
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-204672
VL  - 48
IS  - 401
ER  - 
TY  - JOUR
A1  - Motyka, M.
A1  - Dyksik, M.
A1  - Ryczko, K.
A1  - Weih, R.
A1  - Dallner, M.
A1  - Höfling, S.
A1  - Kamp, M.
A1  - Sęk, G.
A1  - Misiewicz, J.
T1  - Type-II quantum wells with tensile-strained GaAsSb layers for interband cascade lasers with tailored valence band mixing
JF  - Applied Physics Letters
N2  - Optical properties of modified type II W-shaped quantum wells have been investigated with the aim to be utilized in interband cascade lasers. The results show that introducing a tensely strained GaAsSb layer, instead of a commonly used compressively strained GaInSb, allows employing the active transition involving valence band states with a significant admixture of the light holes. Theoretical predictions of multiband k.p theory have been experimentally verified by using photoluminescence and polarization dependent photoreflectance measurements. These results open a pathway for practical realization of mid-infrared lasing devices with uncommon polarization properties including, for instance, polarization-independent midinfrared light emitters.
KW  - modulation spectroscopy
KW  - semiconductors
KW  - Type-II quantum well
KW  - interband cascade laser
KW  - GaAsSb
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189795
VL  - 108
IS  - 10
ER  - 
TY  - JOUR
A1  - Schade, A.
A1  - Bader, A.
A1  - Huber, T.
A1  - Kuhn, S.
A1  - Czyszanowski, T.
A1  - Pfenning, A.
A1  - Rygała, M.
A1  - Smołka, T.
A1  - Motyka, M.
A1  - Sęk, G.
A1  - Hartmann, F.
A1  - Höfling, S.
T1  - Monolithic high contrast grating on GaSb/AlAsSb based epitaxial structures for mid-infrared wavelength applications
JF  - Optics Express
N2  - We demonstrate monolithic high contrast gratings (MHCG) based on GaSb/AlAs0.08Sb0.92 epitaxial structures with sub-wavelength gratings enabling high reflection of unpolarized mid-infrared radiation at the wavelength range from 2.5 to 5 µm. We study the reflectivity wavelength dependence of MHCGs with ridge widths ranging from 220 to 984 nm and fixed 2.6 µm grating period and demonstrate that peak reflectivity of above 0.7 can be shifted from 3.0 to 4.3 µm for ridge widths from 220 to 984 nm, respectively. Maximum reflectivity of up to 0.9 at 4 µm can be achieved. The experiments are in good agreement with numerical simulations, confirming high process flexibility in terms of peak reflectivity and wavelength selection. MHCGs have hitherto been regarded as mirrors enabling high reflection of selected light polarization. With this work, we show that thoughtfully designed MHCG yields high reflectivity for both orthogonal polarizations simultaneously. Our experiment demonstrates that MHCGs are promising candidates to replace conventional mirrors like distributed Bragg reflectors to realize resonator based optical and optoelectronic devices such as resonant cavity enhanced light emitting diodes and resonant cavity enhanced photodetectors in the mid-infrared spectral region, for which epitaxial growth of distributed Bragg reflectors is challenging.
KW  - monolithic grating
KW  - high contrast
KW  - mid-infrared wavelength applications
KW  - epitaxial structures
KW  - GaSb/AlAsSb
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-350346
VL  - 31
IS  - 10
ER  -