N-heteroacenes as an organic gain medium for room temperature masers

The development of future quantum devices such as the maser, i.e., the microwave analog the laser, could be well-served by exploration of chemically tuneable organic materials. Current iterations of room temperature organic solid-state masers are composed of an inert host material that is doped with a spin-active molecule. In this work, we have systematically modulated the structure of three nitrogen-substituted tetracene derivatives to augment their photoexcited spin dynamics and then evaluated their potential as novel maser gain media. To facilitate these investigations, we adopted an organic glass former, 1,3,5-tri(1-naphthyl)benzene (1-TNB) to act a universal host. These chemical modifications impacted the rates of intersystem crossing, triplet spin polarisation, triplet decay and spin-lattice relaxation, leading to significant consequences on the conditions required to surpass the maser threshold.