Photo-Thermoelectric Conversion of Plasmonic Nanohole Array

Abstract

Plasmonic photo-thermoelectric conversion offers an alternative photodetection mechanism that is not restricted by semiconductor bandgaps. Here, we report a plasmonic photodetector consisting of an ultra-thin silver film with nanohole array, whose photodetection mechanism is based on thermoelectric conversion triggered by plasmonic local heating. The detector exhibits a maximum photocurrent at the wavelength of the surface plasmon polaritons, determined by the periodicity of the nanoholes. Hence, the response wavelength of the detector can be controlled via the morphological parameters of the nanohole pattern. The contribution of plasmonic local heating to thermoelectric conversion is verified experimentally and numerically, enabling discussion on the mechanisms governing light detection. These results provide a starting point for the development of other nanoscale photodetectors.

221 K Local Photothermal Heating in a Si Plasmonic Waveguide Loaded with a Co Thin Film

“…The interaction between light and matter with SPP has been applied to optical refractive index sensors with propagating/localized surface plasmon resonance (SPR) [ 6 ], localized surface plasmon with enhanced Raman scattering (SERS) [ 7 ], magnetic modulation of SPP and optical isolator application [ 8 ], and light-induced local heating with metal nanoparticles [ 9 , 10 ]. Light-induced local heating has been applied for thermophoretic manipulation of DNA with Au nanoparticles [ 11 ], resonant light-triggered DNA release from plasmonic nanoparticles [ 12 ], and selective light-induced contents release from liposomes [ 13 ].…”

Optical Metasurfaces for Energy Conversion

“…Their optical response can be precisely tuned to the desired wavelength range and purpose by adjusting the architecture. Contrary, tuning the wavelength regime of bulk material can be rather complex and is achieved by material selection, precise band gap engineering via doping, − alloying, − or morphology modification, , and by the engineering of defect states, , heterojunctions, − or incorporation of tunable nanocrystals or quantum dots. ,, Furthermore, metasurfaces can bring advanced functionalities such as improved response time emerging from their reduced dimensions, and enhanced photoresponse and sensitivity due to longer charge carrier lifetimes originating from their large surface-to-volume ratios. , In addition, metasurfaces offer an interesting bridge between photodetection and photothermal effects offering an alternative photodetection mechanism independent of semiconductor bandgaps. − Thermoelectric devices, where the absorbed electromagnetic radiation is converted to heat raising the temperature of the device resulting in an electron flow, can be utilized as photodetectors when combined with light-absorbing layers. Metasurfaces allow the design of ultrathin absorbers that can be utilized as coatings on commercially available thermoelectric devices .…”

Fabrication of perfect plasmonic absorbers for blue and near-ultraviolet lights using double-layer wire-grid structures

“…Such filters can be divided into three types: filters that transmit light of a specific wavelength, filters that reflect light, and filters that absorb light. Examples include filters used for biosensing [1], infrared spectroscopy [2], solar cells [3][4][5], cooling by heat release [6][7][8], image sensors [9], color filters [10][11][12][13][14][15][16][17][18], detectors [19][20][21], and fluorescence observations [22].…”

“…In this study, we have focused on perfect absorbers, which are one kind of wavelength-selection filter. Perfect absorbers have been studied for visible, infrared, and THz-light applications [2,3,17,[23][24][25][26]. On the contrary, UV applications include bandpass filters [27][28][29][30], band-stop filters [31], and broad-band absorbers from the UV to near infrared [32].…”