Abstract
In this letter, we evaluate the conversion efficiency of thermally isolated Seebeck nanoantennas by numerical simulations and discuss their uses and scope for energy harvesting applications. This analysis includes the simple case of titanium-nickel dipoles suspended in air above the substrate by a 200 nm silicon dioxide membrane to isolate the heat dissipation. Results show that substantially thermal gradients are induced along the devices leading to a harvesting efficiency around 10-4 %, 400 % higher than the previously reported Seebeck nanoantennas. In the light of these results, different optimizing strategies should be considered in order to make the Seebeck nanoantennas useful for harvesting applications.
Highlights
IntroductionThe approach of using resonant nanoantennas for harvesting applications has gained considerable attention over the last decade since they introduce a novel and efficient mechanism to confine light into small volumes, and provide an enabling technology for energy gathering in the visible or infrared region.[1,2,3] Nanoantennas are metallic nanostructures that resonate to the free-propagating electromagnetic waves by inducing a high frequency AC resonant current along their volume.[4,5] This resonant current is subsequently exploited either to sense or recover the electromagnetic energy.[6,7] Different harvesting mechanisms such as the use of fast rectifying diodes coupled to the antennas have been extensively investigated in order to recover this confined energy in an efficient way,[8,9,10,11] thereby opening, a new route for the advanced design of harvesting devices
Seebeck nanoantennas exploit the temperature gradients occurring along their structure which are induced by the resistive heating generated by the resonant current
We evaluate the thermal isolation as a strategy to increase the performance of the Seebeck nanoantennas and discuss their suitability and scope for harvesting applications
Summary
The approach of using resonant nanoantennas for harvesting applications has gained considerable attention over the last decade since they introduce a novel and efficient mechanism to confine light into small volumes, and provide an enabling technology for energy gathering in the visible or infrared region.[1,2,3] Nanoantennas are metallic nanostructures that resonate to the free-propagating electromagnetic waves by inducing a high frequency AC resonant current along their volume.[4,5] This resonant current is subsequently exploited either to sense or recover the electromagnetic energy.[6,7] Different harvesting mechanisms such as the use of fast rectifying diodes coupled to the antennas have been extensively investigated in order to recover this confined energy in an efficient way,[8,9,10,11] thereby opening, a new route for the advanced design of harvesting devices In this regard, Seebeck nanoantennas are devices that have recently reappeared as an alternative to harvest the electrical energy confined by such nanoantennas.[12,13,14,15] These devices are simple nanometersized thermocouples which act as nanoantennas and generate DC power by the Seebeck effect when they operate at resonance. The thermal gradients along the nanometer-sized thermocouples in turn generate a DC Seebeck voltage V OC that can be sensed at the open edges of the nanoantennas;[16,17] defining a transduction mechanism to harvest energy
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have