A compact micro electrical mechanical actuated ring-resonator includes a bus waveguide disposed on a platform; a ring resonator disposed on the platform, including at least a first optical coupler, wherein the ring resonator is optically coupled with the bus waveguide; and a selective waveguide disposed on a piezoelectric cantilever mounted in a trench defined in the platform, wherein the selective waveguide includes a second optical coupler and is controllable to selectively adjust a coupling ratio between the first optical coupler with the second optical coupler by physically changing a distance between the first optical coupler and the second optical coupler.