Temperature sensor and fiber laser based on optical microfiber knot resonator

An easy method to fabricate microfiber-knot resonator (MKR) is designed and its application as a temperature sensor and multi-wavelength fiber laser (MWFL) is demonstrated. The MKR has a temperature sensitivity of 14.5 pm/°C over a temperature range of 27-95 °C, and experimental results show good linearity between the temperature and resonant wavelength shifts. As an MWFL on the other hand, up to four lasing lines with a channel spacing of 4.29 nm are obtained. These results confirm that the MKR could be employed as a high performance comb filter to realize compact optical sensor and MWFL designs.