A light emitting device (10) comprises a body (12) of a semiconductor material. A first junction region (14) is formed in the body between a first region (12.1) of the body of a first doping kind and a second region (12.2) of the body of a second doping kind. A second junction region (16) is formed in the body between the second region (12.2) of the body and a third region (12.3) of the body of the first doping kind. A terminal arrangement (18) is connected to the body for, in use, reverse biasing the first junction region (14) into a breakdown mode and for forward biasing at least part (16.1) of the second junction region (16), to inject carriers towards the first junction region (14). The device (10) is configured so that a first depletion region (20) associated with the reverse biased first junction region (14) punches through to a second depletion region associated with the forward biased second junction region (16).