Knowledge Bank

A new continuously tunable high resolution millimeter/submillimeter wave (mm/submm) source with a spectral purity better than $107$ has been developed. The source consists of a mode locked Ti:Sapphire laser whose 120fs duration pulses are converted to the mm/submm region by means of a subpicosecond pnotoconductive switch. The dominant noise source which limits spectral purity can be traced to fluctuations in the argon ion pump laser. An analysis of the spectral purity and system noise will be presented along with sample spectra of OCS transitions at 340GHz and 607GHz.