In this paper, we report on the growth and characterization of high doping concentration (2.1 at%) ytterbium (Yb) doped lithium niobate (Yb:LiNbO
3) crystal. By using a slightly modified Czochralski method, we have successfully grown a usable size (2 mm × 2
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In this paper, we report on the growth and characterization of high doping concentration (2.1 at%) ytterbium (Yb) doped lithium niobate (Yb:LiNbO
3) crystal. By using a slightly modified Czochralski method, we have successfully grown a usable size (2 mm × 2 mm × 30 mm) Yb:LiNbO
3 single crystal. We also conducted the energy-dispersive X-ray spectroscopy (EDS) and the X-ray diffraction (XRD) analyses, which experimentally confirm that the grown crystal is a Yb:LiNbO
3 single crystal. We also measured the absorption and emission spectra of the grown crystal. It was found out that there is a near-flat broad emission within a spectral range of 1004–1030 nm when excited at 980 nm for this high doping concentration Yb:LiNbO
3 crystal. Such a near-flat broad emission can be very useful for realizing high slope efficiency ultrafast (femtosecond) lasing in the Yb:LiNbO
3 crystal due to the low quantum defect of the Yb:LiNbO
3 crystal. We also investigated the electro-optic effect of the Yb:LiNbO
3. The experimental result confirms that the electro-optic (EO) effect of a highly doped (2.1 at%) lithium niobate crystal is close to the EO value of the pure lithium niobate. Thus, the highly doped Yb:LiNbO
3 crystal can still be an effective electrically tunable lasing medium. It can enable electrically tunable, high slope efficiency femtosecond lasing due to the combined features, including (1) a near flat broad emission spectrum at the spectral range of 1004–1030 nm, (2) a non-compromised electro-optic effect at high doping concentration Yb:LiNbO
3 crystal, and (3) a low quantum defect.
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