Thermo-optical control of L-band lasing in Er-doped tellurite glass microsphere with blue laser diode.

Miniature lasers based on rare-earth ion-doped tellurite microsphere resonators with whispering gallery modes (WGMs) are promising devices for basic research and applications. However, the excitation of WGMs using an external pump is not a simple task requiring passive or active control. We propose and demonstrate the implementation of thermo-optical control of the L-band laser generation in an Er-doped in-band pumped tellurite glass microsphere using a cheap low-power blue laser diode and a constant-wavelength telecom laser as a pump. The proposed scheme ensures simplification and cost reduction of microlasers.