Transformation of a single photon field into bunches of pulses
  We propose a method to transform a single photon field into bunches of pulses with controllable timing and number of pulses in a bunch. This method is based on transmission of a photon through an optically thick single-line absorber vibrated with a frequency appreciably exceeding the width of the absorption line. The spectrum of the quasi-monochromatic incoming photon is 'seen' by the vibrated absorber as a comb of equidistant spectral components separated by the vibration frequency. Tuning the absorber in resonance with m-th spectral component transforms the output radiation into bunches of pulses with m pulses in each bunch. We experimentally demonstrated the proposed technique with single 14.4 keV photons and produced for the first time gamma-photonic time-bin qudits with dimension d=2m. 
R.N. Shakhmuratov, F.G. Vagizov, V.A. Antonov, Y.V. Radeonychev, and   O. Kocharovskaya
quant-ph