Biography
Biography: Sven Hoefling
Abstract
20 years after their first reference interband cascade lasers (ICLs) have become a mature and competitive semiconductor laser source in the mid-infrared region. The carrier rebalancing concept that was introduced in 2011 drastically improved the performance. As a consequence the wavelength window that is accessible for ICLs operating at ambient temperatures could be extended. For GaSb based ICLs cw-emission at room temperature could be achieved up to a wavelength of 5.6 µm. As the need for thicker claddings at longer wavelengths makes the growth of the superlattice claddings increasingly difficult and limits the heat dissipation, a plasmon waveguide structure with highly doped InAs-layers grown on InAs-substrates is typically used for ICLs emitting beyond 6 µm. At cryogenic temperatures plasmon waveguide based ICLs have shown emission up to 10.4 µm. Up to now there has not been an attempt to explore the lower wavelength limit of ICLs. Here we present cw emission of a GaSb based ICL emitting at 2.8 µm and room temperature pulsed operation of an InAs based plasmonic waveguide ICL up to 7.1 µm. Furthermore, we show single mode emitting ICLs with distributed feedback gratings emitting between 2.8 and 5.2 µm.
