Deep level centers and their role in photoconductivity transients of InGaAs/GaAs quantum dot chains

作者：Kondratenko S V^*; Vakulenko O V; Mazur Yu I; Dorogan V G; Marega E Jr; Benamara M; Ware M E; Salamo G J

来源：Journal of Applied Physics, 2014, 116(19): 193707.

DOI：10.1063/1.4902311

The in-plane photoconductivity and photoluminescence are investigated in quantum dot-chain InGaAs/GaAs heterostructures. Different photoconductivity transients resulting from spectrally selecting photoexcitation of InGaAs QDs, GaAs spacers, or EL2 centers were observed. Persistent photoconductivity was observed at 80K after excitation of electron-hole pairs due to interband transitions in both the InGaAs QDs and the GaAs matrix. Giant optically induced quenching of in-plane conductivity driven by recharging of EL2 centers is observed in the spectral range from 0.83eV to 1.0eV. Conductivity loss under photoexcitation is discussed in terms of carrier localization by analogy with carrier distribution in disordered media.

• 出版日期2014-11-21