The student will take part in research regarding infrared emitting phosphors (materials
converting visible light into infrared). Such phosphors, working on the principle of
photoluminescence, absorb photons of higher energy (visible light) and in turn emit
photons of infrared light. Infrared emitting phosphors find numerous applications in
optical sensing, chemical analysis, bioimaging, machine vision, optical communication,
and night-vision surveillance, due to the unique features of infrared light, including
invisibility to the naked eye, exceptional penetrating capability, and low biological tissuerelated
absorption and scattering.
Currently, a great effort is made to find infrared phosphors with desired properties:
specified emission spectrum, high quantum efficiency (ratio between number of emitted
photons to the number of absorbed photons), good stability of emission under elevated
temperature. This can be obtained by choosing the correct chemical composition of the
material (so called crystalline host) and activating the material – introducing to the host
a small amount of different chemical element. These elements (dopants) form isolated
optical centres in the crystal which are responsible for absorbing and emitting infrared
light.
