MEASUREMENT OF PLANCK CONSTANT BASED ON LED QUANTUM THEORY

Planck constant is of great significance in physics. Planck constant can be measured according to LED quantum theory. LED is a common semiconductor device, its electrical and optical characteristics are easily affected by temperature. The threshold voltage and peak wavelength of LED at different temperatures are measured by using a self-made adjustable thermostat to control the temperature of LED. The experimental results show that the threshold voltage of LED decreases and the peak wavelength shifts red with the increase of temperature. Based on the light quantum theory, the threshold voltage and peak wavelength of LED are processed. The threshold voltage and frequency are fitted in a straight line, and Planck constant is obtained from the slope of the fitting line.