Broadband tuning and dual-spectral/temporal outputs from a nonresonantly injection-seeded diode laser

Abstract

We demonstrate spectral narrowing and continuous broadband tuning of the picosecond pulse outputs from a nonresonantly injection-seeded, gain-switched diode laser that can be operated in dual spectral/temporal regimes. A single spectral output was continuously tunable over a range of 85 nm and in a dual-wavelength operation the outputs had spectral separations were adjustable from 3.5 to 53 nm.

Dramatic spectral narrowing and broadband tuning from a self‐injection‐seeded diode laser

“…Without an external cavity, the typical gain-switched pulse durations were ϳ45 ps at repetition frequencies of 1.90 -2.70 GHz with spectral bandwidths up to 20 nm and average powers up to 50 mW. An optical scheme involving one diffraction grating [7] was investigated, in which the feedback obtained by 1 st -order diffraction from the grating with 600 lines/mm was sufficient to reduce the spectral bandwidth from ϳ20 nm to Ͻ0.5 nm, as illustrated in Figure 1. The grating was positioned at distances that were varied from 20 to 70 cm from the laser-diode facet.…”

Tunable and multiple-wavelengths/temporal output from gain-switched diode laser and a four Bragg-grating Fiber

“…An average power of 150 mW (peak power ϳ1.5 W) was achieved with pulses having spectral bandwidths up to 20 nm. 6 The fiber fabricated for this work was designed to provide spectral narrowing and a multiple wavelength/temporal output. By using a chirped phase mask as a 50/ 50 beamsplitter within a Talbot interferometer 7 it was possible to write a Bragg grating within a hydrogen-loaded 980 nm wavelength single mode fiber from Fibercore.…”

Tunable dual-wavelength laser constructed by silicon micromachining

“…Conventional dual-wavelength lasers are mainly based on fiber lasers 1-4 and semiconductor lasers. [5][6][7][8][9] Although the fiber lasers provide attractive features such as narrow linewidth and low noise, they usually require the use of a filter element ͑such as distributed Bragg reflector͒ to select the laser modes. Hence, the majority of demonstrated lasers are constructed with relatively long cavities, which may make it difficult to obtain single longitudinal mode at each desired wavelength position and tends to have undesirable wavelengths due to the sidelobes of the filters.…”