Magnetic on-off switching of a plasmonic laser

The nanoscale mode volumes of surface plasmon polaritons have enabled plasmonic lasers and condensates with ultra-fast operation(1-4). Most plasmonic lasers are based on noble metals, rendering the optical mode structure inert to external fields. Here we demonstrate active magnetic-field control over lasing in a periodic array of Co/Pt multilayer nanodots immersed in an IR-140 dye solution. We exploit the magnetic nature of the nanoparticles combined with mode tailoring to control the lasing action. Under circularly polarized excitation, angle-resolved photoluminescence measurements reveal a transition between the lasing action and non-lasing emission as the nanodot magnetization is reversed. Our results introduce magnetization as a means of externally controlling plasmonic nanolasers, complementary to modulation by excitation(5), gain medium(6,7) or substrate(8). Further, the results show how the effects of magnetization on light that are inherently weak can be observed in the lasing regime, inspiring studies of topological photonics(9-11).

Automated summary

Research has shown that active magnetic-field control over lasing can be achieved in a periodic array of Co/Pt multilayer nanodots immersed in an IR-140 dye solution, allowing for external manipulation of plasmonic nanolasers. By exploiting the magnetic nature of the nanoparticles and mode tailoring, the transition between lasing action and non-lasing emission can be controlled, showcasing a new way to modulate plasmonic lasers. This study also demonstrates how the effects of magnetization on light, typically weak, can be observed in the lasing regime, paving the way for further exploration in topological photonics.