Exciton localization behaviour in different well width undoped GaN/Al₀.₀₇Ga₀.₉₃N nanostructures

• Autorzy: Sabooni M. , Esmaeili M. , Haratizadeh H. , Monemar B. , Paskov P. , Kamiyama S. , Iwaya M. , Amano H. , Akasaki I.
• Języki publikacji: EN

Abstrakty

EN

We report results from optical spectroscopy such as photoluminescence (PL) and time resolved photo-luminescence (TRPL) techniques from different well width MOCVD grown GaN/Al₀.₀₇Ga₀.₉₃N MQW samples. There is evidence of localization at low temperature in all samples. The decay time of all samples becomes non-exponential when the detection energy is increased with respect to the peak of the emission. Localization of carriers (excitons) is demonstrated by the "S-shape" dependences of the PL peak energies on the temperature. The time-resolved PL spectra of the 3-nm well multi quantum wells reveal that the spectral peak position shifts toward lower energies as the decay time increases and becomes red-shifted at longer decay times. There is a gradient in the PL decay time across the emission peak profile, so that the PL process at low temperatures is a free electron-localized hole transition.

Słowa kluczowe

EN

photoluminescence; time-resolved photoluminescence; quantum well; exciton localization; GaN/AlGaN

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2007
• Tom: Vol. 15, No. 3
• Strony: 163--167
• Opis fizyczny: Bibliogr. 21 poz., wykr.

Twórcy

autor

Sabooni M.

autor

Esmaeili M.

autor

Haratizadeh H.

autor

Monemar B.

autor

Paskov P.

autor

Kamiyama S.

autor

Iwaya M.

autor

Amano H.

autor

Akasaki I.

• Departament of Physics, Islamic Azad University, Shahrood Branch, Shahrood, Iran,

Bibliografia

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