Fig. 1. Experimental setup and sample diagrams. (a) OPO laser; (b) microscopic image of 2D sample; (c) microscopic image of microbubble cavity with wall thickness of approximately 1 μm; (d) microscopic image of fluorescence emitted by 3D microbubble cavity containing solid-state fluorescent protein

Fig. 2. Related parameters of fluorescent protein mCherry. (a) Absorption and photoluminescence spectra of mCherry; (b) fluorescence lifetime of mCherry with molecular structure of mCherry shown in inset

Fig. 3. Laser properties of 2D micro-disk. (a) Normalized fluorescence spectrum and laser spectrum of fluorescent protein micro-disk laser; (b) emission spectrum collected by low-resolution grating as a function of pump energy density; (c) high-resolution laser spectrum collected by grating as a function of pump energy density; (d) relationship between laser output intensity and pump energy density with measured data shown by points and fitted curve shown by lines

Fig. 4. Spectral analysis and laser mode simulation of 2D micro-disk cavities. (a) Lorentzian fitting of high-resolution spectral laser peak; (b) schematic of 2D fluorescent protein micro-disk laser and laser mode simulation

Fig. 5. Quality factor measurement of microbubble cavity. (a) Transmission spectrum of whispering-gallery-mode microbubble cavity; (b) quality factor of microbubble cavity

Fig. 6. Laser properties of 3D microbubble. (a) High-resolution laser spectrum collected by grating as a function of pump energy density with bright red laser emitted from edge of solid-state protein microbubble cavity when pump energy density exceeds threshold shown in inset; (b) simulation of laser modes in solid-state fluorescent protein microbubble cavity; (c) relationship between integrated energy and pump energy density with measured data shown by dots and fitted curve shown by line; (d) high-resolution laser spectrum collected by grating