An undulator is proposed based on the plasma wakefields excited by a laser pulse in a
plasma channel. Generation of the undulator fields is achieved by inducing centroid
oscillations of the laser pulse in the channel. The period of such an undulator is proportional
to the Rayleigh length of the laser pulse and can be submillimeter, while preserving high
undulator strength. The electron trajectories in the undulator are examined, expressions for
the undulator strength are presented, and the spontaneous radiation is calculated …

A novel plasma undulator based on the wakefields excited by a laser pulse in a plasma
channel is described. Generation of the undulator fields is achieved by inducing centroid
oscillations of the laser pulse in the channel. The period of such a plasma undulator is
proportional to the Rayleigh length of the laser pulse and can be sub-millimeter, with an
effective undulator strength parameter of order unity. The undulator period can further be
controlled and reduced by beating laser modes or using multiple colors. Analytic …