Nanoantenna-based ultrafast thermoelectric long-wave infrared detectors.

We investigate the generation of electrical signals by suspended thermoelectrically coupled nanoantennas (TECNAs) above a quasi-spherical reflector cavity in response to rapidly changing long-wave infrared radiation. These sensors use a resonant nanoantenna to couple the IR energy to a nanoscale thermocouple. They are positioned over a cavity, etched into the Si substrate, that provides thermal isolation and is designed as an optical element to focus the IR radiation to the antenna.

Cavity-Backed Antenna-Coupled Nanothermocouples.

This paper reports a two-orders-of-magnitude improvement in the sensitivity of antenna-coupled nanothermocouple (ACNTC) infrared detectors. The electrical signal generated by on-chip ACNTCs results from the temperature difference between a resonant antenna locally heated by infrared radiation and the substrate. A cavity etched under the antenna provides two benefits.