Impact ionization coefficients in strained inGaAs/lnAIAs multiquantum wells
نویسندگان
چکیده
We have measured electron and hole impact ionization coefficients in biaxially strained In,Gat -&JIn,,Alll -,,As (0.44 <x <0.62,0.44 <y < 0.62) multiquantum wells for the first time. It is seen that o/a is enhanced due to strain-induced changes in band gap, band offsets, and bandstructure for tensile strain in the well and compressive strain in the barrier. The results have been interpreted by considering band-to-band impact ionization and band-edge discontinuity impact ionization processes.
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