Tuning Characteristics of Frequency Difference for Zeeman-Birefringence He-Ne Dual Frequency Laser

Characteristics of frequency difference tuning of Zeeman-birefringence He-Ne dual frequency lasers (ZBDFLs) are explored. We design an automatic system of tuning cavity and power detection, which can tune the laser cavity and record the tuning curves of light power and frequency difference simultaneously. A synthetical phenomenon by Zeeman effect, mode pulling effect and birefringence effect is verified to exist in ZBDFLs. By analysing the tuning behaviour, this synthetical phenomenon is discovered and qualitatively explained for the first time.