Upconversion

{
  "id": "MLC-T-CHM-012458",
  "term": "Upconversion",
  "field": "Chemistry",
  "definition": "A photophysical process in which the sequential or simultaneous absorption of two or more photons leads to the emission of light at a shorter wavelength, and therefore higher energy, than the excitation photons. This nonlinear optical phenomenon is the opposite of downconversion or fluorescence. Upconversion is observed in specific materials doped with lanthanide ions, such as erbium or thulium.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "downconversion",
    "power"
  ],
  "references": [
    "PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 437 (https://doi.org/10.1351/pac200779030293)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/upconversion/"
}