Near infrared tunable lasers based on flexible polymeric Bragg reflection waveguide devices

Flexible polymer waveguide with an imbedded Bragg grating is incorporated to form an external cavity lasers operating at near infrared wavelength. The third-order Bragg reflection grating imbedded in a polymer waveguide is optimized to produce an appropriate reflection spectrum for NIR-ECL with a center wavelength of 840 nm. Compressive strain and tensile strain were imposed across the flexible polymer device so as to achieve the wavelength tuning of 32 nm. The wavelength peak position was almost linearly proportional to the imposed strain, and the efficiency of wavelength tuning by the imposed strain was 0.9 pm/ μɛ.