  We report on fabrication of a microtoroid resonator of high-quality (high-Q)
factor integrated with an on-chip microheater. Both the microresonator and
microheater are fabricated using femtosecond laser three-dimensional (3D)
micromachining. The microheater, which is located about 200 micron away from
the microresonator, has a footprint size of 200 micron by 400 micron. Tuning of
the resonant wavelength in the microresonator has been achieved by varying the
voltage applied on the microheater. The drifting of the resonant wavelength
shows a linear dependence on the square of the voltage applied on the
microheater. We found that the response time of the microresonator is less than
10 secs which is significantly shorter than the time required for reaching a
thermal equilibrium on conventional heating instruments such as an external
electric heater.
