We study the lasing dynamics of individual ZnO nanorods by time-resolved μ-photoluminescence. The distinct laser modes show gain competition and pronounced shifts as a function of excitation density. This behavior can be understood in terms of many-particle effects within an inverted electron-hole plasma and of the calculated mode spectra of the particular nanorod, whose geometry is known from electron microscope investigations.
J. Fallert, F. Stelzl, H. Zhou, A. Reiser, K. Thonke, R. Sauer, C. Klingshirn, H. Kalt
Optics Express 16, 1125 (2008)