Optical microrings

Grover, R., Ibrahim, T.A., Kanakaraju, S., Lucas, L., Calhoun, L.C., and Ho, P.-T., 2004, A tunable GalnAsP-InP optical microring notch filter, IEEE Photon. Techno Lett. 16(2) 467-469. 

This chapter provides an overview of the basic principles and designs of such sensors. A chemical sensor to detect trace explosives and a broadband fiber optic electric-field sensor are presented as practical examples. The polymers used for the trace explosive sensor are unpoled and have chromophores randomly orientated in the polymer hosts. The electric field sensor uses a poled polymer with chromophores preferentially aligned through electrical poling, and the microring resonator is directly coupled to the core of optical fiber. 

Fig. 2.3 By regarding a basic microring resonator as an optical circuit composed of a directional coupler and a curved waveguide (the cross hatched section), the characteristics of the microring resonator can be analyzed using simpler BPM code and transfer matrices instead of computation intensive FDTD simulation. Reprinted from Ref. 15 with permission. 2008 Institute of Electrical and Electronics Engineers...

Passaro, V. M. N. Dell Olio, F. Leonardis, F. D., Ammonia optical sensing by microring resonators, Sensors 2007, 7, 2741 2749... 

During the thermal-reflow process, waveguides are reshaped from a rectangular shape to a mushroom one. Slight deformation does not affect the microring optical performance, but only shift its resonance position. However, too high reflow temperature and/or too long process time can dramatically deform the cross section... 

Huang, Y. Paloczi, G. T. Scheuer, J. Yariv, A., Soft lithography replication of polymeric microring optical resonators, Opt. Exp. 2003, 11, 2452 2458... 

Rezzonico, D. Jazbinsek, M. Guarino, A. Kwon, O. Gunter, P., Electro optic Charon polymeric microring modulators, Opt. Exp. 2008, 16, 613 627... 

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