Simultaneous four-photon luminescence, third-harmonic generation, and second-harmonic generation microscopy of GaN.
We demonstrate what is to our knowledge the first example of four-photon luminescence microscopy in GaN and apply it to quality mapping of bulk GaN. The simultaneously acquired second- and third-harmonic generation can be used to map the distribution of the piezoelectric field and the band-tail state density, respectively. Through spectrum- and power-dependent studies, the fourth power dependence of the band edge luminescence is confirmed. The superb spatial resolution of the four-photon luminescence modality is also demonstrated. This technique provides a high-resolution, noninvasive monitoring and tool for examining the physical properties of semiconductors.
Chu
Shi-Wei
SW
Graduate Institute of Electro-Optical Engineering, National Taiwan University, Taipei 10617, Taiwan.
Chan
Ming-Che
MC
Tai
Shih-Peng
SP
Keller
Stacia
S
DenBaars
Steven P
SP
Sun
Chi-Kuang
CK