Solar blind chemically vapor deposited diamond detectors for vacuum ultraviolet pulsed light-source characterization

A major difficulty in characterizing vacuum ultraviolet (VUV) radiation pro duced by harmonic generation or four-wave sum frequency mixing arises in di fferentiating between the desired VUV signal and the remaining fundamental pump laser beam. To overcome this problem, visible and near UV blind VUV de tectors, made from natural and synthetic diamond, have been developed. Such detectors have been used to characterize coherent VUV pulses (lambda = 125 nm, pulse duration at full width half maximum (FWHM) tau(FWHM)similar to 7 ns) generated by resonance-enhanced four-wave sum mixing in mercury vapor. They allow full characterization of the intensity profile of the VUV pulse s, without any significant parasitic signal from simultaneous stray light i rradiation at lambda = 313 nm. Detectors were fabricated exhibiting respons e times of less than 70 ps at FWHM, corresponding to the lowest response ti me obtainable with a 7 GHz bandwidth single-shot oscilloscope. (C) 1998 Ame rican Institute of Physics. [S0021-8979(98)05520-0].