Efficient Chemical Sensing by Coupled Slot SOI Waveguides

Sensors

Vittorio M. N. Passaro¹  Francesco Dell'Olio²  Caterina Ciminelli² 

[1] id="af1-sensors-09-01012">Dipartimento di Elettrotecnica ed Elettronica, Politecnico di Bari, via Edoardo Orabona n. 4, 70125 Bari, Ita

关键词: Integrated optics;    Optical sensor;    Slot waveguides;    Silicon-on-insulator;   

DOI  :  10.3390/s90201012

来源: mdpi

【 摘 要 】

A guided-wave chemical sensor for the detection of environmental pollutants or biochemical substances has been designed. The sensor is based on an asymmetric directional coupler employing slot optical waveguides. The use of a nanometer guiding structure where optical mode is confined in a low-index region permits a very compact sensor (device area about 1200 μm²) to be realized, having the minimum detectable refractive index change as low as 10^-5. Silicon-on-Insulator technology has been assumed in sensor design and a very accurate modelling procedure based on Finite Element Method and Coupled Mode Theory has been pointed out. Sensor design and optimization have allowed a very good trade-off between device length and sensitivity. Expected device sensitivity to glucose concentration change in an aqueous solution is of the order of 0.1 g/L.

【 授权许可】

CC BY   
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.