  We present a nano-scale photoelectron source, optimized towards ultrashort
pulse durations and well-suited for time-resolved diffraction experiments. A
tungsten tip, mounted in a suppressor-extractor electrode configuration, allows
the generation of 30 keV electron pulses with an estimated pulse duration of 37
fs at the gun exit. We infer the pulse duration from particle tracking
simulations, which are in excellent agreement with experimental measurements of
the electron-optical properties of the source. We furthermore demonstrate
femtosecond laser-triggered operation. Besides the short electron pulse
duration, a tip-based source is expected to feature a large transverse
coherence as well as a nanometric emittance.
