Title: population inversion
Long Title: IUPAC Gold Book - population inversion
DOI: 10.1351/goldbook.P04759
Status: current

Definition
A situation in which a higher energy state is more populated than a lower energy state.

Source
- PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2266 (https://doi.org/10.1351/pac199668122223)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/P04759/html
- json: https://goldbook.iupac.org/terms/view/P04759/json
- xml: https://goldbook.iupac.org/terms/view/P04759/xml

Citation: Citation: 'population inversion' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.P04759
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Accessed: 2026-05-12T18:01:40+00:00