Microjoule Ultrafast Yb-Fiber Laser in Tunable Repetition-Rate

Ultrafast laser delivering microjoule (μJ) level pulse energy has been widely used in scientific, medical and industrial applications, such as nonlinear frequency conversion [1], vision correction in ophthalmology [2], and material precision micro-machinging [3]. Take vision correction for example, current commercial laser applied in corneal structural modifications are operated in a fixed repetition rate (rep-rate), such as 500 kHz or 2 MHz for the VisuMax series from Carl Zeis. Fix the rep-rate helps to reduce the system complexity in constructing femtosecond lasers. However, it is powerless when confronting applications necessitating femtosecond pulse with larger pulse energy at a lower rep-rate, such as performing cataract surgery. Hence, a μJ-level pulse energy ultrafast laser operating in a tunable rep-rate could provide great flexibility in dealing with applications demanding femtosecond pulse with different parameters.