Resonant Thermoelectric Nanophotonics
Abstract
Photodetectors are typically based either on photocurrent generation from electron–hole pairs in semiconductor structures or on bolometry for wavelengths that are below bandgap absorption. In both cases, resonant plasmonic and nanophotonic structures have been successfully used to enhance performance. Here, we show subwavelength thermoelectric nanostructures designed for resonant spectrally selective absorption, which creates large localized temperature gradients even with unfocused, spatially uniform illumination to generate a thermoelectric voltage. We show that such structures are tunable and are capable of wavelength-specific detection, with an input power responsivity of up to 38 V W^(–1), referenced to incident illumination, and bandwidth of nearly 3 kHz. This is obtained by combining resonant absorption and thermoelectric junctions within a single suspended membrane nanostructure, yielding a bandgap-independent photodetection mechanism. We report results for both bismuth telluride/antimony telluride and chromel/alumel structures as examples of a potentially broader class of resonant nanophotonic thermoelectric materials for optoelectronic applications such as non-bandgap-limited hyperspectral and broadband photodetectors.
Additional Information
© 2017 Macmillan Publishers Limited, part of Springer Nature. Received 10 June 2016; Accepted 31 March 2017; Published online 22 May 2017. This work was supported primarily by the US Department of Energy (DOE) Office of Science grant DE-FG02-07ER46405. S.K. acknowledges support by a Samsung Scholarship. The authors thank M. Jones for discussions. Author Contributions: K.W.M. and H.A.A. conceived the ideas. K.W.M. and S.K. performed the simulations. K.W.M. fabricated the samples. K.W.M. built the measurement set-ups specific to this study. K.W.M., S.M. and D.F. performed measurements, and K.W.M., S.K. and S.M. performed data analysis. K.S. contributed to the design and analysis of noise measurements. R.P. built a general-use measurement set-up and provided assistance with part of one supplementary measurement. K.W.M., H.A.A. and S.M. co-wrote the paper. All authors discussed the results and commented on the manuscript, and H.A.A. supervised the project. The authors declare no competing financial interests.Attached Files
Submitted - 1606.03313.pdf
Supplemental Material - nnano.2017.87-s1.pdf
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Additional details
- Eprint ID
- 70797
- DOI
- 10.1038/NNANO.2017.87
- Resolver ID
- CaltechAUTHORS:20161004-090725146
- Department of Energy (DOE)
- DE-FG02-07ER46405
- Samsung Scholarship
- Created
-
2016-10-04Created from EPrint's datestamp field
- Updated
-
2021-11-11Created from EPrint's last_modified field
- Caltech groups
- JCAP, Kavli Nanoscience Institute