The blood–brain barrier (BBB) is a specialized semipermeable structure that highly
regulates exchanges between the central nervous system parenchyma and blood vessels …

Opportunities for enhancing solar energy harvesting using photon upconversion are
reviewed. The increasing prominence of bifacial solar cells is an enabling factor for the …

Using light to control matter has captured the imagination of scientists for generations, as
there is an abundance of photons at our disposal. Yet delivering photons beyond the surface …

Triplet states have been widely studied in phosphorescent molecules, lanthanide complexes
and triplet–triplet annihilation systems, in which they have a critical role in energy transfer …

Optical nanomaterials have been widely used in anticounterfeiting applications. There have
been significant developments powered by recent advances in material science, printing …

Abstract Ultraviolet (UV, λ< 400 nm) light is essential for various photochemical reactions,
but its intensity in the solar spectrum is very low, and light sources that artificially generate …

Upconversion is a nonlinear optical phenomenon that involves the emission of high‐energy
photons by sequential absorption of two or more low‐energy excitation photons. Due to their …

Rare-earth (RE) doped nanoparticles show unique features of photon conversion from an
incident wavelength to a more suitable wavelength at an intended biological site, thus …

Upconversion nanocrystals have been extensively investigated for optical imaging and
biomedical applications,. However, their photoluminescence is strongly attenuated by …

The increasing demand for the multidimensional and dynamic control of light has spurred
the development of stimuli‐responsive, reconfigurable, and programmable optical systems …