Solid State Defect Emitters With no Electrical Activity.

Point defects may introduce defect levels into the fundamental bandgap of the host semiconductors that alter the electrical properties of the material. As a consequence, the in-gap defect levels and states automatically lower the threshold energy of optical excitation associated with the optical gap of the host semiconductor. It is, therefore, a common assumption that solid-state defect emitters in semiconductors ultimately alter the conductivity of the host. This study demonstrate, on a particular defect in 4H silicon carbide, that an unrecognized class of point defects exists that are optically active but electrically inactive in the ground state.