2ND-ORDER ZEEMAN-EFFECT IN THE 5(2)S-3(2)S AND 4(2)D-3(2)S 2-PHOTON TRANSITIONS OF ATOMIC SODIUM

We have observed the second-order, field-induced Zeeman effects of the Doppler-free two-photon transitions 5 S-2-3(2)S and 4 D-2-3(2)S of at omic sodium using fields up to 5 T. Using a suitable experimental conf iguration it was possible to avoid the appearance of first-order effec ts in the high-field limit. The remaining small field-induced shifts a re of the order of magnitude of a few linewidths. They yield the diffe rences of the diamagnetic susceptibilities of the connected atomic sta tes. The method is therefore capable of providing data related to atom ic electronic structure.