Light-matter interaction of Exciton Polaritons at Telecommunication Wavelengths (LIEPOLATE)

该提案的目标是演示1.31 μm波长范围内的激子-极化激元激光器。这将通过在GaAs衬底上生长的新型稀氮化物材料与用于制造高质量微腔结构的已建立的GaAs基技术相结合来实现。由于稀氮化物量子威尔斯（QW）能够在1.31 μm附近的电信窗口中发射（这是传统的GaAs上的无氮QW无法达到的），这种新方法将允许研究QW激子与微腔的光子模在电信波长处的强耦合。在优化稀氮化物量子阱质量之后，特别是在高结构均匀性、减少横向组成波动和载流子局部化方面，这些发射器将被并入微腔中以将该系统驱动到强耦合制度中。在这里，形成了被称为激子-极化激元的杂化准粒子。如果超过临界粒子数密度，激子-极化激元可以在基态凝聚，并且观察到所谓的极化激元激光的开始，这与光子激光相反，在没有粒子数反转的情况下发生。这允许在电信波长处实现超低阈值激子-极化激元激光器件。此外，该提案中设想的发展将揭示与激子-极化激元相关的迷人性质的研究的新可能性，例如超流现象，量子相变，逻辑器件等。

This proposal targets the demonstration of an exciton-polariton laser in the 1.31 μm wavelength range. This will be enabled by the combination of novel dilute nitride materials grown on GaAs substrates in combination with established GaAs-based technology for the fabrication of high quality microcavity structures. Since dilute nitride quantum wells (QWs) enable emission in the telecommunication window around 1.31 μm (which is inaccessible with conventional nitrogen-free QWs on GaAs), this new approach will allow studies of the strong coupling of a QW exciton with a photonic mode of a microcavity at telecom wavelengths. After optimization of the dilute nitride QW quality, especially in terms of high structural homogeneity, reduced lateral composition fluctuations and carrier localization, these emitters will be incorporated into microcavities to drive this system into the strong-coupling regime. Here, hybridized quasi-particles called exciton-polaritons are formed. Exciton-polaritons can condense in the ground state if a critical population density is exceeded, and one observes the onset of so-called polariton lasing, which in contrast to photon lasers occurs without population inversion. This allows the realization of ultra-low threshold exciton-polariton laser devices at telecom wavelengths. In addition, the developments envisaged in this proposal will reveal new possibilities for studies of the fascinating properties related to exciton-polaritons, like e.g. superfluid phenomena, quantum phase transitions, logic devices, etc. at telecommunication wavelengths.