Self-Induced Mode-Locking in Electrically Pumped Far-Infrared Random Lasers.

ABSTRACT: Mode locking, the self-starting synchronous oscillation of electromagnetic modes in a laser cavity, is the primary way to generate ultrashort light pulses. In random lasers, without a cavity, mode-locking, the nonlinear coupling amongst low spatially coherent random modes, can be activated via optical pumping, even without the emission of short pulses. Here, by exploiting the combination of the inherently giant third-order χ⁽³⁾ nonlinearity of semiconductor heterostructure lasers and the nonlinear properties of graphene, the authors demonstrate mode-locking in surface-emitting electrically pumped random quantum cascade lasers at terahertz frequencies. This is achieved by either lithographically patterning a multilayer graphene film to define a surface random pattern of light sca

SUBMITTER: Di Gaspare A 

PROVIDER: S-EPMC10037977 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature