  How to utilize topological microcavities to control quantum emission is one
of the ongoing research topics in the optical community. In this work, we
investigate the emission of quantum emitters in doubly-resonant topological
Tamm microcavity, which can simultaneously achieve dual resonances at two
arbitrary wavelengths according to the needs of practical application. To
achieve the enhancement of quantum emission in such cavities, we have exploited
the tunable doubly-resonant modes, in which one of resonant modes corresponds
to the pump laser wavelength and the other one is located at the emission
wavelength of quantum emitters. Both theoretical and experimental results
demonstrate that the pump excitation and emission efficiencies of quantum
emitters are greatly enhanced. The main physical mechanism can be explained by
the doubly-resonant cavity temporal coupled-mode theory. Furthermore, we
observe the faster emission rate and the higher efficiency of unidirectional
quantum emission, which have promising applications in optical detection,
sensing, filtering, and light-emitting devices.
