We study the phenomenon of synchronization in pairs of doubly clamped,
mechanically coupled silicon micro-oscillators. A continuous-wave laser beam is
used to drive the micro-beams into limit cycle oscillations and to detect the
oscillations using interferometry. Devices of different dimensions are used to
introduce frequency detuning, and short silicon bridges connecting the
micro-beams are used as mechanical coupling between the oscillators. The region
of synchronization is plotted for the MEMS system in the detuning vs. coupling
parameter space and compared with the numerical analysis of a corresponding,
lumped-parameter model. Three states of oscillations are observed i.e. the
drift state, quasi-periodic state, and the synchronized state. The numerical
model also distinguishes between in-phase and out-of-phase synchronization
where out-of-phase synchronization is observed at low coupling strengths and
low frequency detuning. We also show that the experimentally measured frequency
fluctuations of the system reduce with an increase in coupling strength.Comment: 8 pages, 7 figure