Enhancement of the luminescence response of subwavelength lattices of Si disks with embedded GeSi quantum dots when switching from a simple lattice to a lattice with a basis

The effect of the lattice basis modification of photonic crystal on the luminescence properties of emitters embedded in them was studied. The photonic crystals were square lattices of subwavelength Si disks with embedded GeSi quantum dots. The basis was modified by changing the size of the disks in one of the sublattices with a doubled period. A microphotoluminescence study revealed that this change in the photonic crystal structure leads to a multiple increase in the intensity of individual photoluminescence peaks in the emission region of the GeSi quantum dots. A theoretical calculation of the emissivity of the studied structures confirms that the observed effect is based on an increase in the local density of optical states in the modified structure.