Experimental study of two-dimensional photonic crystals [Review] [French]

摘要

Photonic bandgap materials (PBGs), the so-called photonic crystals, are structures With a periodic dielectric constant. For strong enough index contrast, it was theoretically predicted that they should prevent light propagation in all directions, because they create spectral regions with zero-density of states. We study the optical properties of two-dimensional photonic crystals etched through waveguiding semiconductor heterostructures. Photoluminescence of quantum wells or quantum dots embedded in the waveguide are used as internal probe source. This technique allows a full characterization of these objects, giving access to quantitative values of the transmission, reflection and diffraction coefficients. Weak transmissions correspond to high reflection or diffraction values, which indicates that light remains guided upon interaction with the crystals, confirming their high potential for integrated optics. These reflectors are next used as cavity mirrors. One-dimensional cavities demonstrate a high finesse through transmission measurements, confirming the low amount of out-of-plane losses. Small volume three-dimensional cavities (similar to 5 mum(3)) are also probed, using the photoluminescence of the emitters placed inside the cavity. Narrow peaks in the photoluminescence spectrum prove the strong confinement and allow to envision applications for spontaneous emission control. [References: 153]