Fig. 1. Schematic of fiber coupled double microsphere resonators, and diagrams of light propagation in microsphere resonators. (a) Schematic of fiber coupled double microsphere resonator; (b) light propagation in single microsphere resonator; (c) upper light propagation in double microsphere resonators; (d) lower light propagation in double microsphere resonators

Fig. 2. Simulated reflectance spectra of single microsphere coupled resonator and double microsphere coupled resonators. (a) Single microsphere coupled resonator; (b) double microsphere coupled resonators

Fig. 3. Schematic of splicing of SMF and capillary, placing the single microsphere resonator and double microsphere resonators into the capillary, and micrograph of the developed fiber coupled double microsphere resonators. (a) Schematic of splicing of SMF and capillary; (b) placing the single microsphere resonator into the capillary; (c) placing the double microsphere resonators into the capillary; (d) micrograph of the developed fiber coupled double microsphere resonators

Fig. 4. Reflection spectrum measurement setup for fiber coupled double microsphere resonators

Fig. 5. Reflection spectra of device without microsphere resonator, single microsphere coupled resonator, and double microsphere coupled resonators. (a) Reflection spectrum of device without microsphere resonator; (b) reflection spectrum of single microsphere coupled resonator; (c) reflection spectrum of double microsphere coupled resonators

Fig. 6. FFT of reflection spectra of single microsphere coupled resonator and double microsphere coupled resonators. (a) FFT of reflection spectrum of single microsphere coupled resonator; (b) FFT of reflection spectrum of double microsphere coupled resonators

Fig. 7. Reflection spectra and temperature response in the temperature increasing experiments. (a) Reflection spectra; (b) temperature response

Fig. 8. Reflection spectra and temperature response in the temperature decreasing experiments. (a) Reflection spectra; (b) temperature response