Controlling electron spin states with light is vital for quantum technologies but requires electronic excitations with net spin. Now a molecular diradical with two trityl radical groups coupled via a meta-linked fluorene bridge has been developed that features luminescent singlet and triplet excitons. The spins in the ground state can be written and read using photons, giving rise to broad magnetic and microwave modulation of the photoluminescence.
- Rituparno Chowdhury
- Petri Murto
- Richard H. Friend