Topological Laser

The cascade of resonant PT-symmetric topological structures is shown to emit laser light with a frequency comb spectrum. We consider optically active topological lattices supporting edge modes at regularly spaced frequencies. When the amplified resonances in the PT-broken regime match the edge modes of the topological gratings, we predict the emission of discrete laser lines. A proper design enables the engineering of the spectral features for specific applications. Topological protection makes the system very well suited for a novel generation of compact frequency comb emitters for spectroscopy, metrology, and quantum information.



L.Pilozzi and C.Conti
Topological cascade laser for frequency comb generation in -symmetric structures
Opt. Lett. 42, 5174 (2017).


L.Pilozzi and C.Conti
Topological lasing in resonant photonic structures
Phys. Rev. B 93, 195317(2016).