Ultrashort-pulse modulation in adiabatically prepared Raman media Sarah Gundry, Marcel P. Anscombe, Abubaker M. Abdulla, Emiliano Sali, John W. G. Tisch, Paul Kinsler, Geoffrey H. C. New, and Jon P. Marangos Blackett Laboratory, Imperial College London, Prince Consort Road, South Kensington, London SW7 2BZ, United Kingdom Optics Letters 30, 180-182 (2005). We demonstrate the efficient modulation of an 100-femtosecond pulse in a Raman medium coherently prepared by nanosecond pulses. Raman sidebands of the ultrashort pulse spanning 360 THz are generated with an efficiency of >5%. We show that the mechanism permitting the sidebands to be generated is the preparation of a significant vibrational coherence in the medium that is robust to disturbance by the intense short pulse. If the observed sidebands were phase compensated, they would form a short train of approximately ten 3-fs pulses. Focusing would permit the realization of a peak intensity of >10^13 W/cm^2.