Polariton-condensation effects on photoluminescence properties in a CuBr microcavity

6th International Conference on Optical, Optoelectronic and Photonic Materials and Applications 2014

Nakayama, Masaaki^1 ; Murakami, Katsuya^1 ; Furukawa, Yoshiaki^1 ; Kim, Daegwi^1

Department of Applied Physics, Graduate School of Engineering, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka

558-8585, Japan^1

关键词: Cavity polariton;    Condensation effects;    Electron hole plasma;    Excitation power dependence;    Lower polariton branches;    Photogenerated electrons;    Photoluminescence properties;    Threshold excitation power;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/619/1/012015/pdf
DOI  :  10.1088/1742-6596/619/1/012015

来源: IOP

【 摘 要 】

We have investigated the photoluminescence (PL) properties in a CuBr microcavity with HfO2/SiO2distributed Bragg reflectors at 10 K from the viewpoint of cavity-polariton condensation. From the excitation-power dependence of PL spectra detected at an in-plane wave vector of k||=0, we found that the PL characteristics of the lower polariton branch markedly change with a threshold nature: a drastic increase (decrease) in the intensity (band width). In addition, the PL energy exhibits a large blueshift, ∼10 meV, around the threshold excitation power, reflecting strong polariton-polariton interactions. The blueshifted PL energy is far below the bottom energy of the cavity photon. In addition, the estimated density of photogenerated electron-hole pairs at the threshold excitation power is two orders lower than the Mott-transition density for the formation of electron-hole plasma. The above results consistently demonstrate the occurrence of the cavity-polariton condensation.