The influence of the p-n junction induced electric field on the optical properties of InGaN/GaN/AlGaN light emitting diode

The temperature dependence of photoluminescence measurement was performed on an undoped ${\mathrm{In}}_{\mathrm{0.126}}{\mathrm{Ga}}_{\mathrm{0.874}}\mathrm{N/GaN}$ multiple quantum well (MQW) structure and a light emitting diode (LED) structure using this MQW as an active region. The emission energy of the LED structure showed a red shift of about 230 meV at room temperature compared with the undoped ${\mathrm{In}}_{\mathrm{0.126}}{\mathrm{Ga}}_{\mathrm{0.874}}\mathrm{N/GaN}$ MQW. This behavior of the LED structure is attributed to the quantum-confined Stark effect due to its $\mathrm{p-n}$ junction induced electric field. This conclusion was confirmed by a calculation and a detailed discussion based on the theory of the quantum-confined Stark effect.