Development of Coupled-Cavity Laser Diodes for Remote Sensing

Several recent developments in diode laser technology such as multiple emitter phase-locked arrays and epitaxial growth of materials that can be used to make lasers which emit at wavelengths ranging from the visible through the near infrared make these devices attractive candidates as sources for spectroscopic applications and remote sensing systems. The perceived advantages of diode lasers include efficiency, small size and weight, and direct modulation capability. But in fact mode hopping under current modulation, wavelength drift with temperature, and their relatively broad linewidths make conventional diode lasers less than ideal sources for laser spectroscopy. Elaborate stabilization schemes and external cavities are often used to overcome these shortcomings.