Research Topics of Lasers Group

InP based Laser diodes are being developed for a variety of applications in the area of optical tele- and data communications, and sensors. This development work mainly aims at improving laser performance as well as reducing costs related to processing, testing, and eventually packaging. Depending on the specific device the wavelength range between about 1200 nm and 1900 nm is covered. Bulk-InGaAsP-, QW-InGaAsP-, QW-InGaAlAs-, combinations thereof, and most recently also quantum dot (QD) structures are used as active layer.

Our current research, development, design and fabrication activities cover the following topics:

  • Fabry-Perot and DFB laser diodes with tapered output for high coupling efficiency
  • DFB lasers for 10…28 Gb/s uncooled direct modulation
  • EMLs for 10…100 Gb/s direct modulation
  • surface emitting DFB lasers (HCSEL, horizontal cavity design)
  • DFB lasers for sensing applications and other industrial applications
  • medium power DFB lasers up to 150 mW
  • high power broad area FP lasers with >4 W CW and >16 W pulse optical power (300ns pulses)
  • gain chips for external cavity lasers;
  • DFB lasers, SOAs, and RSOAs for flip chip hybrid integration with Si-, SiN and Polymer PICs
  • Mode locked lasers as wavelength comb sources


 All devices are completely fabricated at HHI using our InP processing line. Characterisation and chip selection is carried out using an automatic bar measurement system. Mounted devices can be fully characterised with respect to all relevant laser parameters such as e.g. output power, optical far-field, modal gain, optical losses, relative intensity noise (RIN), frequency response, chirp, phase noise and linewidth.

Top view of Curved Stripe DFB (CSDFB) - Laser
Front facet of Horizontal Cavity Surface Emitting Laser (HCSEL)
Mounted HCSEL-Laser
40 Gbit/s Directly Modulated Laser
EML device and corresponding eye diagram