Events

Seminar of Physics of Wrocław University of Technology

Nitride Semiconductor Laser Diodes, or How to Teach an Insulator to Behave Like a Semiconductor

Prof. Piotr Perlin

Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland

Wide-bandgap semiconductors such as AlN, GaN, InN, and their ternary alloys can emit light across a broad spectral range—from ultraviolet (UV) to red—and have therefore become an attractive platform for optoelectronic applications. Laser diodes emitting in the UV–visible range are in high demand across many fields. However, nitride-based wide-bandgap semiconductors remain among the least inherently suitable material systems for laser diode fabrication. This is due to several fundamental challenges, including difficulties in doping (particularly p-type doping), strong internal electric fields arising from piezoelectric and pyroelectric effects in hexagonal heterostructures, the lack of lattice matching between binary compounds, and limitations related to the availability and quality of suitable substrates for epitaxial growth. In this seminar, I will show that these seemingly fundamental obstacles can be overcome, enabling the development of a wide variety of nitride-based laser devices tailored for applications ranging from copper welding to atomic optical clocks.