Internet of things: Sensing without power.

Sensor networks detecting rare events, such as a fire or an intrusion, must be both sensitive and selective, such that no important events are missed yet no false alarms are triggered. Using conventional sensing and electronic signal processing, constant vigilance and sophisticated discrimination ability come at the expenses of significant steady-state power consumption. To address the growing need for ubiquitous autonomous intelligent sensing for the Internet of Things requires a rethinking of this tradeoff. Writing in Nature Nanotechnology, Qian et.al.[1] now show a micromechanical signal transduction to create an infrared light sensor that achieves high sensitivity and optical wavelength selectivity while consuming no electrical power. The sensor operates in the thermal, mid-infrared region of the optical spectrum. The detected radiation energy actuates a micromechanical relay, providing a digital (on/off) electrical readout.