title: Generalized n-photon resonant 2n-wave mixing in an (n+1)-level system with phase-conjugate geometry.
abstract: A generalized scheme for phase-conjugate resonant 2n-wave mixing, which has a high efficiency and is easy for phase matching, is proposed. As a new type of coherent laser spectroscopy this approach can be employed for studying highly excited atomic states or states with a high angular momentum. To demonstrate its feasibility we have studied the doubly excited autoionizing Rydberg states of Ba by phase-conjugate six-wave mixing, and have furthermore achieved eight-wave mixing in Na. This method may find wide application in related areas such as coherent transient spectroscopy, Autler-Townes spectroscopy and electromagnetically induced transparency. In particular, it may provide new insights into the nature of highly excited states.
authors.affiliation: Laboratory of Optical Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Zhanchun
authors.initials: Z
authors.lastname: Zuo
authors.forename: Jiang
authors.initials: J
authors.lastname: Sun
authors.forename: Xia
authors.initials: X
authors.lastname: Liu
authors.forename: Qian
authors.initials: Q
authors.lastname: Jiang
authors.forename: Guangsheng
authors.initials: G
authors.lastname: Fu
authors.forename: Ling-An
authors.initials: LA
authors.lastname: Wu
authors.forename: Panming
authors.initials: P
authors.lastname: Fu