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arXiv · 1805.04043

THz Transient Photoconductivity of the III-V Dilute Nitride GaPAsN

J. N. Heyman·E. M. Weiss·J. R. Rollag·K. M. Yu·O. D. Dubon·Y. J. Kuang·C. W. Tu·W. Walukiewicz
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Abstract

THz Time-Resolved Photoconductivity is used to probe carrier dynamics in the dilute III-V nitride GaP0.49As0.47N0.036. In these measurements a femtosecond optical pump-pulse excites electron-hole pairs, and a delayed THz pulse measures the change in conductivity. We find the photoconductivity is dominated by localized carriers. The decay of photoconductivity after excitation is consistent with bimolecular electron-hole recombination with recombination constant r = 3.2E-8 +/-0.8E-8 cm3/s. We discuss the implications for applications in solar energy.

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J. N. Heyman, E. M. Weiss, J. R. Rollag, K. M. Yu, O. D. Dubon, Y. J. Kuang, C. W. Tu, W. Walukiewicz. 2018-05-10. THz Transient Photoconductivity of the III-V Dilute Nitride GaPAsN. https://doi.org/10.1088/1361-6641/aae7c5

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