An all-optical tunable polymer WGM laser pumped by a laser diode

Area of Science:

• Photonics
• Materials Science
• Optoelectronics

Background:

• Whispering gallery mode (WGM) lasers are crucial for integrated optics.
• Tunable lasers are essential for various spectroscopic and sensing applications.
• Developing efficient and stable all-optical tuning mechanisms remains a challenge.

Purpose of the Study:

• To propose and demonstrate an all-optical tunable WGM laser.
• To investigate the thermo-optic effect for wavelength tuning.
• To evaluate the laser's performance in terms of tuning range, efficiency, stability, and response time.

Main Methods:

• Fabrication of a WGM laser by filling a silica capillary with a conjugated polymer solution.
• Utilizing auxiliary laser irradiation to induce thermo-optic effects for tuning.
• Characterizing the emission wavelength shift with varying irradiation power intensity.

Main Results:

• Continuous wavelength tuning over 13 nm was achieved.
• A tuning rate of 0.58 nm W⁻¹ cm⁻² was observed.
• Fast response time (< 2.8 s) and high operational stability (> 100 minutes) were demonstrated.
• Good repeatability and high tuning efficiency were confirmed.

Conclusions:

• The proposed all-optical tunable WGM laser offers a promising solution for on-chip light sources.
• The thermo-optic effect in polymer-filled capillaries provides an effective tuning mechanism.
• The laser's performance characteristics make it suitable for integrated photonic devices.