A trion is a localized excitation which consists of three charged quasiparticles. A negative trion consists of two electrons and one hole and a positive trion consists of two holes and one electron.

Trion Decay in Colloidal Quantum Dots
Excitonic trion X - in semiconductor quantum wells
Fine structure of the quantum-dot trion
All-optical trion generation in single-walled carbon nanotubes
Trion, biexciton, and exciton dynamics in single self-assembled CdSe quantum dots
Oscillator strength of trion states in ZnSe-based quantum wells
Functional renormalization for trion formation in ultracold fermion gases
Exciton and trion spectral line shape in the presence of an electron gas in GaAs/AlAs quantum wells
Fine structure of the trion triplet state in a single self-assembled semiconductor quantum dot
SANDOWNIA HARRISI, A HIGHLY DERIVED TRIONYCHOID TURTLE (TESTUDINES: CRYPTODIRA) FROM THE EARLY CRETACEOUS OF THE ISLE OF WIGHT, ENGL...