“…Secondly, Yb 3+ -doped laser materials also possess numerous excellent characteristics, such as no excited state absorption, no cross relaxation, a broad absorption and emission bandwidth, a small quantum defect and low thermal loading. In recent years, various kinds of Yb 3+ -doped lasers realized mode-locking operations either with the help of saturable absorbers such as semiconductor saturable absorber mirrors (SESAM) [1][2][3][4], single wall carbon nanotubes (SWCNT) [5][6][7][8], grapheme [9,10], graphene oxide [11], or by means of Kerr-lens mode-locking (KLM) [12]. KLM is a promising technique in diode-pumped solid state Yb 3+ lasers for generating sub-100 fs pulses.…”