We demonstrate a C-band wavelength-tunable microlaser with an Er3+ doped high
quality (~1.02x10^6) lithium niobate microdisk resonator. With a 976 nm
continuous-wave pump laser, lasing action can be observed at a pump power
threshold as low as ~250 {\mu}W at room temperature. Furthermore, the microdisk
laser wavelength can be tuned by varying the pump laser power, showing a tuning
efficiency of ~-17.03 pm/mW at low pump power blow 13 mW, and 10.58 pm/mW at
high pump power above 13 mW