High-injection behavior of InGaAs quantum well

Spontaneous emission spectra are investigated of mode-free strained-layer InGaAs/GaAs quantum well structures in wide range of injection current (up to ∼32 kA/cm 2 ). The spectral bandwidth increases along with the current increase up to ∼6 kA/cm 2 at 4.2 K, and above this current it begins to narrow. We find non-monotone shift of the main spectral peak at low temperature. Possible origin of this behavior is suggested if the low-current peak can be associated with exciton emission whereas the higher-current peak - with electron-hole plasma recombination. The competition of two shifts occurs: blue one due to reducing the exciton binding energy by free-carrier screening and red one by many-body interaction. In the limit of low current at 4.2 K, the spectral band is fitted by simple sech-type function, which is in as the homogeneous line shape function. This line shape is explained as a result of the non-Markovian collisional broadening.

[1]  Michael Schreiber,et al.  Numerical Experiments on the Absorption Lineshape of the Exciton under Lattice Vibrations. I. The Overall Lineshape. , 1982 .

[2]  Akihisa Tomita,et al.  A new density matrix theory for semiconductor lasers, including non-Markovian intraband relaxation and its application to nonlinear gain , 1991 .

[3]  Petr G. Eliseev,et al.  Emission of strained-layer InGaAs quantum well under high-injection level: study of bandfilling and broadening effects , 1996, Photonics West.

[4]  T. Ohtoshi,et al.  Optical line shape functions in quantum-well and quantum-wire structures , 1991 .

[5]  Goetz Erbert,et al.  Study of strained-layer InGaAs/GaAs SQW RW lasers including analysis of internal coupling of modes and antiguiding effects , 1994, Photonics West - Lasers and Applications in Science and Engineering.

[6]  Chih-Hung Wu,et al.  Coulomb enhancement in InGaAs-GaAs quantum-well lasers , 1997 .

[7]  Fred H. Pollak,et al.  Temperature dependence of the photoreflectance of a strained layer (001) In0.21Ga0.79As/GaAs single quantum well , 1991 .

[8]  Y. Toyozawa,et al.  Theory of Line-Shapes of the Exciton Absorption Bands , 1958 .

[9]  Götz Erbert,et al.  Power hysteresis and waveguide bistability of stripe quantum-well InGaAs/GaAs/GaAlAs heterolasers with a strained active layer , 1995 .

[10]  P G Eliseev,et al.  Emission from quantum-well InGaAs structures , 1998 .

[11]  F. Urbach.  The Long-Wavelength Edge of Photographic Sensitivity and of the Electronic Absorption of Solids , 1953 .