Symmetry
plays an essential role in the fundamental properties
of a physical system. In this work, we report on the realization of
tunable single-mode polariton lasing from highly excited Rydberg states
via symmetry engineering. By breaking the symmetry of the polaritonic
wave function through potential wells and controlling the spatial
overlap between the gain region and the eigen mode, we are able to
generate single-mode polariton lasing, reversibly and dynamically,
from quantized polariton states. Increasing the asymmetry of the potential
well, single-mode lasing can be achieved even for the highly excited
Rydberg state with a principle quantum number of N = 14. Moreover, as a result of the excellent reservoir–eigen
mode overlap and efficient spatial confinement, the threshold of lasing
can be reduced up to 6 orders of magnitude, compared with those conventional
pumping schemes. Our results present a new strategy toward the realization
of thresholdless polariton lasing with dynamical tunability.