Search

In this study, we propose a polarization-separated external cavity feedback structure based on a volume Bragg grating (VBG) that folds the optical path of a free-running diode laser into a non-straight direction for linewidth narrowing and central wavelength locking. By employing diode laser polarization splitting technology and external cavity feedback technology, a similar output power and narrow linewidth but a smaller current drift coefficient of central wavelength are demonstrated by comparing with the standard straight external cavity feedback structure. Experimental results show that the current drift coefficient of central wavelength reduce to 1/5 that of the traditional method. According to our research, this is the first report on folding the extended external cavity feedback optical path in a non-straight direction basing on polarization splitting technology, providing a new method for external cavity feedback based on the VBG. • A polarization-separated external cavity feedback structure based on a VBG for linewidth narrowing and central wavelength locking is proposed. • A similar output power and narrow linewidth but a smaller current drift coefficient of central wavelength are demonstrated. • The locked central wavelength as a function of operating current shifts at a rate of approximately 2.625 pm/A. [ABSTRACT FROM AUTHOR]

Single-longitudinal-mode end-emitting laser with 10 periods of metal slots at around 956 nm has been fabricated. 100 μm wide broad-stripe and ten periods of 9.5 μm periodicity metal slots are defined by i-line lithography and dry etching. Experimentally, continuous-wave power of 213 mW has achieved, at a slope efficiency of 520 mW/A, having a 3 dB spectrum width of less than 0.04 nm at 900 mA, and operating in a stable single longitudinal mode with the side-mode suppression ratio (SMSR) of 42 dB. We prove that metal slots introduce sufficient loss into the cavity to filter out the wanted mode, and is more efficient on our chip structure than traditional slot laser. This paper provides a new method for the realizing high power broad-stripe (~100 μm) laser and array with single longitudinal mode operation. [ABSTRACT FROM AUTHOR]