Robust lasing modes in coupled colloidal quantum dot microdisk pairs using a non-Hermitian exceptional point.

ABSTRACT: Evanescently coupled pairs of microdisk lasers have emerged as a useful platform for studying the non-Hermitian physics of exceptional points. It remains an open question how scalable and versatile such phenomena can be when carried over to other designs. Here we have studied the effect of gain/loss modulation in an evanescently coupled pair of microdisk optical resonators fabricated from solution-processed colloidal quantum dots. The emission spectra of these structures are sensitive to small imperfections, which cause frequency-splitting of the whispering gallery modes. Despite this inherent disorder, we found that when spatially modulating the optical pump to vary the gain differential between the coupled microdisks, the coupling drives the split parasitic intra-cavity modes into coales

SUBMITTER: Lafalce E 

PROVIDER: S-EPMC6362135 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature