  Octave-spanning, 12.5 fs, (1.9 cycle) pulses with 115 {\mu}J energy in the
short-wavelength mid-infrared spectral range (1-2.5 {\mu}m) have been generated
via phase-mismatched cascaded nonlinear frequency conversion using organic DAST
crystal. Such ultra-fast cascading effect is ensured by the interaction of a
pump pulse with the exceptionally large effective nonlinearity of the DAST
crystal and experiencing non-resonant, strongly phase mismatched, Kerr-like
negative nonlinearity.
