Photoresponse of InGaAs/GaAs multiple-period very-long-wavelength quantum well infrared photodetectors

• DOI: 10.1007/s11082-014-0106-x
• Publication Date: 2014-12-27T00:27:07Z
• Authors: X. Q. Lu; D. Y. Xiong; X. Tong
• Keywords: Photocurrent; Photoconductivity; Quantum Efficiency

We study the photogenerated carriers and photoreponsivity of very-long-wavelength ( $$\sim $$ 17.0 $$\upmu \hbox {m}$$ ) InGaAs/GaAs quantum well infrared photodetectors (QWIPs). By calculating the density of photogenerated carriers in the continuum above the GaAs barriers, we have demonstrated that photocarriers transport from one InGaAs quantum well to the next in the form of Bloch waves. By including the elementary mechanisms involved in the photoresponse process in a self-consistent way, we have obtained the photocurrent, photoresponsivity and detectivities of the InGaAs/GaAs QWIPs. The obtained photocurrent and photoresponsivity were in good agreement with the experiments.