Application of the nonlinear crystal SrB/sub 4/O/sub 7/ for ultrafast diagnostics down to 125 nm

We used non-phase-matched SHG in the highly-nonlinear but low-birefringent crystal SrB/sub 4/O/sub 7/ for temporal characterization (autocorrelation) of femtosecond UV pulses converting them to wavelengths as low as 125 nm, close to the transparency limit of SrB/sub 4/O/sub 7/.