Nonlinear Parametric Scattering of Exciton Polaritons in Perovskite Microcavities

Abstract

Comparing with pure photons, higher nonlinearity in polariton systems has been exploited in various proof-of-principle demonstrations of efficient optical devices based on the parametric scattering effect. However, most of them demand cryogenic temperatures limited by the small exciton binding energy of traditional semiconductors or exhibit weak nonlinearity resulting from Frenkel excitons. Lead halide perovskites, possessing both a large binding energy and a strong polariton interaction, emerge as ideal platforms to explore nonlinear polariton physics toward room temperature operation. Here, we report the first observation of nonlinear parametric scattering in a lead halide perovskite microcavity with multiple polariton branches at room temperature. Driven by the scattering source from condensation in one polariton branch, correlated polariton pairs are obtained at high k states in an adjacent branch. Our results strongly advocate the ability to reach the nonlinear regime essential for perovskite polaritonics working at room temperature.

Direct measurement of a non-Hermitian topological invariant in a hybrid light-matter system

“…Unlike previous observations of EPs in optical microcavities (54), our demonstration of a non-Hermitian topological invariant relies on hybrid light-matter particles, exciton polaritons, which exhibit strong interactions due to the exciton component (63). Therefore, our study offers a new platform for investigating the interplay between the non-Hermitian topology and nonlinearity, which may bring about unexpected phenomena, e.g., similar to self-adaptation in energy transfer (64).…”

Perovskite polariton parametric oscillator

“…[20][21][22] Thanks to S-shaped polariton dispersion, the idler at a high k (wavevector) state and the signal at the ground state can be obtained when two polaritons are resonantly pumped at the inflection point, obeying the conservation law of both energy and momentum. [23][24][25] In addition to this nondegenerate polariton oscillator geometry, in a system with multiple branches, two polaritons at the lowest energy of one polariton branch can scatter to momentum-degenerate states [26][27][28] or energy-degenerate states [29][30][31][32] at adjacent polariton branches. The large third-order polaritonic nonlinearity promotes the realization of polariton oscillators at lower threshold, which has been demonstrated in a variety of semiconductor microcavities.…”

“…The large third-order polaritonic nonlinearity promotes the realization of polariton oscillators at lower threshold, which has been demonstrated in a variety of semiconductor microcavities. [23][24][25][26][27][28][29][30][31][32] Compared with the conventional OPOs, the polaritonic configuration is more versatile and suitable for the realization of quantum correlation and parametric down-conversion toward miniaturized, integrated devices. 22,[28][29][30] So far, polariton oscillators in GaAs or CdTe-based quantum wells demand cryogenic temperatures due to the small exciton binding energy, whereas polariton oscillators have not been realized in organic microcavities due to the low nonlinearity of Frenkel excitons.…”

“…[41][42][43][44] Moreover, the strong nonlinear polariton-polariton interaction has been demonstrated in both 2D hybrid perovskites and 3D all-inorganic perovskites. 32,45 Combining these advantages, halide perovskites provide a promising platform for nonlinear polaritonic devices with low thresholds. Although energy-degenerate parametric scattering has been reported in 3D all-inorganic perovskites, the fixed wavelength of the signal and idler is not adjustable.…”

Relaxation Oscillations of an Exciton-polariton Condensate Driven by Parametric Scattering

“…Because of this interaction, peculiar scattering processes, which are responsible for the nonlinearities, relaxation and thermalization of exciton-polaritons, can thus occur. Great effort has been devoted to the nonlinear polariton scattering processes, parametric scattering in particular [21][22][23][24][25][26], in recent years. Compared with their optical counterpart, polariton parametric scatterings exhibit much higher parametric conversion efficiency [22], making them a promising candidate for the realization of on-chip micro-parametric oscillators.…”