An Amrita paper titled A Sensor for Detection of Contaminants in Water was accepted for the presentation at the International Conference on Electronics and Communication Engineering organized by the Institute for Research and Development, India (IRDI) in Bangalore this past April.

The paper authored by Mr. Alok Kumar Jha, Assistant Professor, Department of Electronics and Communication Engineering (ECE), Amrita School of Engineering, Bangalore explored the possibility of detecting contaminants present in water using photonic crystal sensors, propagating light through them.

Dr. T. Srinivas, Associate Professor, Indian Institute of Sciences, Bangalore co-authored this paper along with Ms. Pooja Deshmukh and Dr. Preeta Saran.

“Our goal was to design a sensor, that could be fabricated as a lab-on-a-chip sensor, to detect impurities in water. The use of photonic crystals should help reduce the response time as well as the size and cost of the sensor system,” Alok shared.

The paper quoted the World Savvy Monitor Report that states that water-borne diseases were the primary cause of death worldwide. Millions of people, many of them children, lose their lives every year from drinking contaminated water.

Common contaminants present in water include bacteria and viruses as well as arsenic, fluoride, nitrates and iron. There is an acute need for sensors that ensure safety of drinking water systems.

“Photonic sensor technology paves a way for the development of modern biosensors. Light propagation in photonic crystals can be engineered by altering the refractive index of the material,” explained Alok.

“In the paper, we proposed the design of a 2-D photonic crystal based sensor with line defects which can detect unsafe contaminants and micro-organisms in water. Bacteria, viruses, hazardous chemicals like lead, mercury, arsenic, can be identified with the help of this sensor. Analytical work has been done with help of simulation tool MIT Photonic Band (MPB) and MIT Electromagnetic Equation Propagation (MEEP),” he added.

“Here the frequency spectrum of light that can propagate through the guided path in a photonic crystal depends on the refractive index of the contaminant present, which is different for the various contaminants. Thus frequency spectrum of the light propagating through the guided path can help us identify various chemical and microbiological pollutants,” he further explained.

Alok expressed that both he and his team members were happy to have had the opportunity to contribute for the good of society, mankind and the environment.

September 4, 2013
School of Engineering, Bangalore