Femtosecond Ionization Source for Ultrahigh Resolution Time-of-flight Mass Spectrometry

High resolution time-of-flight mass spectrometers (TOFMSs) have broad potential application in space exploration. We propose a novel femtosecond electron ionization (El) source which, when coupled to a compact TOFMS, could improve mass resolution of miniature instruments by orders of magnitude, enabling effective isobar identification in volatile and planetary atmospheres. The ionization source is an ultrashort pulsed electron gun triggered by a femtosecond UV laser. In addition, the ultrafast laser technology may also be used for other analytical capabilities like laser desorption/ionization on solid samples, therefore future developments may offer a novel compact instrument package for both atmosphere and surface analysis. Here, we show a series of advances toward this goal, including efficient (5%) generation of 105 fs UV pulses, production of electron bunches of up to 32 fC pC via UV photoemission, and calculations for an ultrafast EI source.