Nanoparticles ordered in periodic arrays provide electromagnetic resonances called surface lattice resonances (SLRs) leading to a high degree of local field confinement. If dye molecules are added on top of the nanoparticle arrays the system can be in the strong coupling regime. Typically, nanoparticle arrays consist
of metals which, however, provide very high losses. In contrast, high-index dielectrics are low-dissipative and can therefore lead to narrower SLRs and therefore to longer lifetimes.
In this work, we fabricate dielectric nanoparticle arrays made out of germanium and amorphous silicon. The SLRs of germanium and amorphous silicon nanoarrays are measured and compared to the SLRs of gold nanoarrays. A quality factor of up to 1.27 higher is provided by the SLRs of dielectric nanoarays compared to the SLRs of the gold nanoarrays. In addition, we measure the dispersion of the nanoarrays with fluorescent dye molecules on top and observe an indication of strong coupling
