Mid-infrared resonant cavity light emitting diodes operating at 4.5 µm.

We report on a mid-infrared resonant cavity light emitting diode (RCLED) operating at the wavelength of 4.5 µm with a narrow spectral linewidth at room temperature. Compared to a reference LED without a resonant cavity, our RCLED exhibits (85x) higher peak intensity, (13x) higher integrated output power, (16x) narrower spectral linewidth and (7x) superior temperature stability.