Resonant Absorption in GaAs-Based Nanowires by Means of Photo-Acoustic Spectroscopy
Petronijevic,E.; Leahu,G.; Belardini,A.; Centini,M.; Li Voti,R.; Hakkarainen,T.; Koivusalo,E.; Guina,M.; Sibilia,C. (2018-03-01)
This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited
Julkaisun pysyvä osoite on
Semiconductor nanowires made of high refractive index materials can couple the incoming light to specific waveguide modes that offer resonant absorption enhancement under the bandgap wavelength, essential for light harvesting, lasing and detection applications. Moreover, the non-trivial ellipticity of such modes can offer near field interactions with chiral molecules, governed by near chiral field. These modes are therefore very important to detect. Here, we present the photo-acoustic spectroscopy as a low-cost, reliable, sensitive and scattering-free tool to measure the spectral position and absorption efficiency of these modes. The investigated samples are hexagonal nanowires with GaAs core; the fabrication by means of lithography-free molecular beam epitaxy provides controllable and uniform dimensions that allow for the excitation of the fundamental resonant mode around 800 nm. We show that the modulation frequency increase leads to the discrimination of the resonant mode absorption from the overall absorption of the substrate. As the experimental data are in great agreement with numerical simulations, the design can be optimized and followed by photo-acoustic characterization for a specific application.
- TUNICRIS-julkaisut 
Näytetään aineisto, joilla on samankaltaisia nimekkeitä, tekijöitä tai asiasanoja.
Smirnov,Sergey; Gotchev,Atanas; Hannuksela,Miska
IEEE International Conference on Multimedia and Expo (2013)
Joint de-noising and fusion of 2D video and depth map sequences sensed by low-powered tof range sensor Georgiev,Mihail; Gotchev,Atanas; Hannuksela,Miska
IEEE International Conference on Multimedia and Expo (Institute of Electrical and Electronics Engineers IEEE, 2013)
Georgiev,Mihail; Gotchev,Atanas; Hannuksela,Miska
IEEE International Symposium on Circuits and Systems (Institute of Electrical and Electronics Engineers IEEE, 2013)