Increased tuning range of Pb1-xSnxSe diode lasers using small magnetic fields

A Pb0.96Sn0.04Se laser diode emitting in the 815-835- cm^-1region with current tuning has been examined with applied magnetic fields at 7 kG and below. With increasing magnetic field the laser gain curve broadens, allowing more laser cavity modes (separated by 1.8 cm^-1) to oscillate at a given current, and yielding a larger tuning range with current for each cavity mode. Using a combination of current tuning and a constant magnetic field, laser emission was achieved from 800 to 850 cm^-1with 90 percent coverage of the spectral interval.