TY - JOUR
T1 - Influence of conduction-band non-parabolicity on terahertz intersubband Raman gain in GaAs/InGaAs step asymmetric quantum wells
AU - Tiutiunnyk, A.
AU - Pérez-Quintana, I.
AU - Laroze, D.
AU - Duque, C. A.
AU - Mora-Ramos, M. E.
N1 - Publisher Copyright:
© 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
PY - 2020/1/1
Y1 - 2020/1/1
N2 - The conduction electron states in step-like strained GaAs/InGaAs quantum wells are theoretically investigated under the effective mass approximation, taking into account the effects of band non-parabolicity. With such information, the intersubband three-level Raman gain is calculated looking to reveal a possible application of the studied systems as sources for THz Raman lasing. A group of high-gain intersubband transitions is identified, and the results are strongly dependent on a suitable geometric design in terms of potential well widths which can lead to values of the Raman gain between 200 and 400cm-1, the latter values being close to those previously reported in GaAs-based double asymmetric quantum wells. Secondary radiation frequencies are identified within the range of few tens of THz. It is found that the influence of band non-parabolicity causes a significant reduction of the Raman gain, in comparison with the values obtained neglecting such a phenomenon. Therefore, conduction-band non-parabolicity becomes a crucial element for the accurate quantitative description of the intersubband-related optical response in low-dimensional heterostructures involving small gap materials.
AB - The conduction electron states in step-like strained GaAs/InGaAs quantum wells are theoretically investigated under the effective mass approximation, taking into account the effects of band non-parabolicity. With such information, the intersubband three-level Raman gain is calculated looking to reveal a possible application of the studied systems as sources for THz Raman lasing. A group of high-gain intersubband transitions is identified, and the results are strongly dependent on a suitable geometric design in terms of potential well widths which can lead to values of the Raman gain between 200 and 400cm-1, the latter values being close to those previously reported in GaAs-based double asymmetric quantum wells. Secondary radiation frequencies are identified within the range of few tens of THz. It is found that the influence of band non-parabolicity causes a significant reduction of the Raman gain, in comparison with the values obtained neglecting such a phenomenon. Therefore, conduction-band non-parabolicity becomes a crucial element for the accurate quantitative description of the intersubband-related optical response in low-dimensional heterostructures involving small gap materials.
UR - https://www.scopus.com/pages/publications/85076820142
U2 - 10.1007/s00339-019-3214-4
DO - 10.1007/s00339-019-3214-4
M3 - Article
AN - SCOPUS:85076820142
SN - 0947-8396
VL - 126
JO - Applied Physics A: Materials Science and Processing
JF - Applied Physics A: Materials Science and Processing
IS - 1
M1 - 23
ER -