Measuring Thermally-Driven LED Emissions via Voltage Modulation near Zero Bias

Abstract

This study was launched to demonstrate that LEDs at zero bias show recombination photon emissions, and to check the models for the same. A method for measuring the light emission for a LED near zero bias is presented. A large reverse bias sufficient to suppress detectable emissions is assumed. The bias voltage between ‘large reverse’ and our target voltage is modulated, and the difference measured. The measured emissions found are consistent with the Shockley diode equation. The spectrum near zero bias can be measured and characterized. It shows LED behavior that is substantially different from other typical measurements, and suggests a violation of Kirchhoff’s Law.