Optical parametric oscillations in 1D microcavities : Strong and weak coupling regime.
Résumé
The recent development of interbranch optical parametric oscillation (OPO) in 2D vertical coupled microcavities (MCs) [1] or wire shaped 1D-MCs [2] opens new paths towards the implementation of monolithic micro-OPOs for the realization of solid sate quantum emitters. It is now well established that very large χ3 polaritonic non-linearities in semiconductor MCs operating in the strong-coupling regime (SC) can be used in order to achieve low-threshold OPO [3]. In conventional planar single MCs the required phase-matching can be obtained thanks to the peculiar band dispersion ruled by the SC of excitons and photons. Nevertheless, in single planar MCs several drawbacks limit their use as a realistic device: (i) the required SC is achieved only at low temperature, (ii) the pump laser must be adjusted to a specific angle, (iii) signal (S) and idler (I) beams are intrinsically strongly un-balanced. Based on multibranch photonic bands dispersion of triply-resonant 2D vertical coupled MCs, interbranch parametric scattering can be achieved in the weak coupling regime (WC) thus leading to higher operating temperature [1]. Still S and I were strongly unbalanced limiting the possible uses of this original system. In the present work we use a different approach for achieving efficient generation of OPOs both in SC and in the WC based on the use of 1D-MCs. The multi-branch fan of the photonic modes in 1D-MCs offers different solutions for the realization of OPOs based on the polarization inversion mechanism (see the schemes over imposed on Fig. 1)[2]. So far vertical processes (S and I split in energy and degenerate in momentum space) were demonstrated in this system (see as an example SV and IV in the left panel of Fig. 2) leading to large differences in S and I intensities (as in the case of triply resonant 2D vertical coupled MCs). Here, by choosing horizontal processes (S and I degenerate in energy and split in momentum space), we generate balanced S and I with the additional advantage of their spatial separation (see as an example SH and IH in Fig. 2 a) and the power dependece in Fig.2 b)). Most important, the OPOs regime is achieved and studied both at 10K in the strong-coupling regime, as well as above 100K in the weak-coupling regime [4]. References [1] C. Diederichs et al., Nat., 440 (2006), pp. 904. [2] G. Dasbach et al., Phys. Rev. B, 71 (2005) pp. 161308R. [3] P. G. Saviddis et al., Phys. Rev. Lett. 84 (2000), pp. 1547. [4] M. Abbarchi et al., in progress