Graphene Terahertz Plasmon Laser: A Laser in a Circuit

We show that as a result of strong field confinement plasmons in population inverted graphene can experience extremely large gain through the process of stimulated emission at terahertz frequencies. The large gain values and the small plasmon wavelengths can lead to compact terahertz plasmon lasers that are only a few microns in size. We present designs for practical terahertz plasmon lasers and discuss schemes for achieving population inversion.