Pressure–Wavelength Relationship of the 6328-Å Helium–Neon Laser Emission*

Abstract

Fundamental wavelength measurements of the 6328-Å radiation emitted by a helium-neon laser, wavelength stabilized with reference to the Lamb dip, have been made at various pressures of 3He and 20Ne. It has been possible to distinguish the particular effects of helium and neon by making two series of observations, the first at constant neon pressure with the helium pressure varied, the second at constant helium pressure and at various pressures of neon. A blue shift proportional to pressure has been obtained in both cases. The corresponding equation for 3He pressures (p) from 1 to 4 torr and for a constant 20Ne pressure of 0.35 torr is λ=0.632 991 499 µm-30.64·10-9·p and for 20Ne pressures from 0.2 to 1.2 torr and a constant 3He pressure of 2.45 torr λ=0.632 991 433 µm-19.4·10-9·p.