  Microcavity exciton-polaritons are two-dimensional bosonic quasiparticles
composed by excitons and photons. Using model Hamiltonian with parameters
generated from ab initio density-functional theory and Bathe-Salpeter Equation
calculations, we investigate the exciton and the exciton-polariton properties
of hexagnonal boron nitride (hBN) based microcavity. We show that hBN based
microcavities, including monolayer and all-dielectric ones, are promising in
optoelectronic applications. Room temperature exciton-polariton Bose-Einstein
Condensation can be achieved because of the large oscillating strength and
binding energy of the exciton, and the strong interaction between the
exciton-polaritons and the longitudinal optical phonons. Based on this BEC
state, exciton-polariton mediated superconducting device can also be fabricated
at such moderate temperatures using the microcavity structure proposed by
Laussy et al.
