Анотація:
The laser oscillation at room temperature in Cr²⁺:ZnS waveguide thin-film
structures under electrical pumping with the impact excitation mechanism was first
discovered after improvement of some waveguide optical properties. However, lasing
turned out to be unstable and ceases soon, which is accompanied by strong weakening
the emission recorded from the waveguide edge whereas the emission from the structure
face remains intensive. It is shown that the above changes stem from increasing optical
losses caused by appearance of light scattering in the structure by inhomogeneities
formed during lasing as a consequence the most probably of recrystallization processes in
the Cr:ZnS film. Some ways are proposed to improve the lasing stability