Influence of the 3d2 3P0 and 3d2 3P2 valence states on the Stark spectrum of the Rydberg state of Ca

Abstract The Stark spectrum of the Ca atom has been investigated in the vicinity of the n = 10–13 transitions by using two-step excitation and photoionization methods with an applied electric field up to 8 kV/cm. The results indicate that the 3 d 2 3 P 0 and 3 d 2 3 P 2 valence states are repelled by the n = 12 Stark manifold. Interference has been observed for the 3 d 2 3 P 0 state and the Stark states and is enhanced as the electric field is increased. The crossing and anticrossing structures of levels among the zero-field non-degenerate states, valence states, and Stark states are also discussed.