Long-term frequency stabilized and linewidth-narrowed cw-laser system for excitation of lithium Rydberg states

We transfer the frequency stability from a diode laser, which was locked to Doppler-free saturation absorption resonance in lithium vapor cell, to a tunable Ti-sapphire laser. We get the laser linewidth < 100 kHz/100 ms and absolute frequency stability ±0.5 MHz. The uv laser system which included the stabilized Ti-sapphire laser and frequency doubler has output optical beam with power near 100 mW and wavelength 350 nm. This uv laser system will be used for excitation and study of Rydberg states in lithium atoms.