International comparison of /sup 127/I/sub 2/-stabilized He-Ne Lasers at /spl lambda//spl ap/633 nm using the third and the fifth harmonic locking technique

In an international comparison of /sup 127/I/sub 2/-stabilized helium-neon lasers at /spl lambda//spl ap/633 nm, lasers from the CMI and the BIPM were stabilized by the third (THT) and the fifth (FHT) harmonic locking techniques. A frequency shift to the blue was measured when using the FHT technique. The influence of weak components of the rotational-vibrational transition P(33) 6-3 of the molecule /sup 127/I/sup 129/I on the frequency shift of components d, e, f, and g of the line R(127) 11-5 is evaluated.<
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