Generation of weak sub-Poissonian light by a high-efficiency light-emitting diode

Weak sub-Poissonian light was generated with a high-efficiency light-emitting diode (LED). The lowest intensity of sub-Poissonian light generated in our experiment was about thousand times as small as those of previous experiments. As an injection current to LED decreased, the mean emission efficiency lowered at room temperature and the frequency response worsened at liquid nitrogen temperature. These phenomena were interpreted in terms of trap states.