VI Systems develops novel yellow laser diode emitting at 599 to 605 nm
The new laser diode emits intrinsically in the orange-yellow region, important for biomedical use.
For laser diodes (LDs) emitting in the visible spectrum, there has always existed a spectral gap in the yellow-orange region where room-temperature LD semiconductor materials can't be made to emit. This has now changed: researchers at VI Systems (Berlin, Germany), along with others from St. Petersburg Academic University and Ioffe Institute (both in St. Petersburg, Russia), Peter Grünberg Institut (Jülich, Germany), and CEMES–CNRS (Toulouse, France) have developed an LD that intrinsically emits in the yellow-orange spectral range from 599 to 605 nm wavelengths at room temperature in a laboratory environment.
The device emits a narrow beam in the vertical direction (fast axis) with a full width at half maximum (FWHM) of 24°. A total of 0.8 W optical output power in pulsed mode operation was realized for a laser with a 1 mm cavity length and 50 µm stripe width, being limited by the catastrophic optical damage of unpassivated uncoated mirrors.
Today, commercially available LD devices in this spectral range are based exclusively on frequency doubling of the laser light from an infrared laser diode by means of a nonlinear crystal.
The new LDs are based on aluminum gallium indium phosphide [(AlxGa1–x)0.5In0.5P] on GaAs substrates.
Laser diodes in the yellow-orange range can be used as compact wearable sources for medical blood control applications, eye surgery, in displays, industrial spectroscopic analysis, sensing, and compact optical atomic clocks with better than than 10−16 frequency uncertainty.
VI Systems will present info on these lasers at the 2018 Advanced Research Workshop Future Trends in Microelectronics (FTM) June 10-16, 2018, Vingt Ans Après, Sardinia, Italy.
Source: VI Systems
1. N. N. Ledentsov et al., Optics Express (2018); https://doi.org/10.1364/OE.26.013985.