The invention comprises a composite material comprising a host material in which are incorporated semiconductor nanocrystals. The host material is light-transmissive and/or light-emissive and is electrical chargetransporting thus permitting electrical charge transport to the core of the nanocrystals. The semiconductor nanocrystals emit and/or absorb light in the near infrared spectral range. The nanocrystals cause the composite material to emit/absorb energy in the near infrared (NIR) spectral range, and/or to have a modified dielectric constant, compared to the host material. The invention further comprises electro-optical devices composed of this composite material and a method of producing them. Specifically described are light emitting diodes that emit light in the NIR and photodetectors that absorb light in the same region.