Photonic crystal QCLs
We design a surface emission QCL device using a photonic crystal. Instead of a grating, a photonic crystal is used to diffract light out of the surface. This laser operates at a band-egde of the energy-momentum space mode which is characterised by low group velocity region as a result of the optical feedback of the lattice.
![Simulated magnetic field emission at the surface of photonic crystal QCLs](https://www.sp.phy.cam.ac.uk/files/media/104um-1rs.jpg)
Figure 1: Simulated magnetic field emission at the surface of photonic crystal QCLs.
![SEM image of nano-structured QCLs](https://www.sp.phy.cam.ac.uk/files/media/120207-2rs.jpg)
Figure 2: SEM image of nano-structured QCLs.