Frequency Stabilization of Argon Lasers at 582.49 THz Using Saturated Absorption in¹²⁷I₂

Abstract

Preliminary results are given for the Allan variance of argon lasers stabilized on iodine saturation peaks in external absorption cells at 5145 Å (10-10 m). A prestabilization on Fabry-Perot transmission fringes was found necessary for the commercial lasers used in this work. A flicker floor at 8 × 10-13 is reached between 0.1 and 1 second. Line pressure broadening and shift are studied by the frequency offset locking technique. This new optical frequency standard appears to offer many advantages with respect to accuracy because of the high molecular weight of I2 and of the possibility of using narrow three level resonances free of recoil structure.