Sub-Femtosecond Bunch Length Diagnostic

The determination of the longitudinal bunch profile of light sources requires ever- increasing precision. As novel schemes to create bunches at the level of tens of femtoseconds become more widespread, the diagnosis of these bunches with increased resolution is necessary. Currently available techniques have resolutions on the order of tens of femtoseconds, but there is no technique that surpasses the femtosecond barrier. The measurement of ultrashort beams in the time domain is accomplished by encoding the temporal profile information on a transverse angular modulation of the beam. This modulation is then observable on a distant screen using readily available imaging tools. Commercial applications and other benefits: The proposed structure will allow the study of beam events on the sub-femtosecond time scale. This addresses needs of modern-day and future accelerators and light sources that necessitate precise resolution of longitudinal beam parameters. The resolution of the scheme is on the order of 1/200 of the laser wavelength, which can be used in other applications, such as precision timing systems, or as an optical streak camera, or fast oscilloscope with greater than 10THz bandwidth.