Double-exponential refractive index sensitivity of metal–semiconductor core–shell nanoparticles: the effects of dual-plasmon resonances and red-shift

Abstract

We present a new type of localized surface plasmon resonance (LSPR) sensor whose refractive index sensitivity can be improved by greatly increasing the plasmon wavelength red-shift of metal–semiconductor core–shell nanoparticles (CSNs).

High-sensitivity refractive index of Au@Cu2−xS core–shell nanorods

“…As we know, spherical nanoparticles exhibit the poorest sensitivities. Based on our early work, 21 the sensitivity of Au@Cu 2Àx S core-shell nanoparticles saturates when the ratio of the shell-thickness to core-radius is close to 3. Furthermore, the performance of the sensor can be usually measured by the gure of merit (FoM).…”

“…For the core-shell nanoparticles, the shell thicknesses also have the important effect on the LSPR shi. 21,33,34 To avoid the impact of aspect ratio of CSNRs, the aspect ratio is xed to 1.6. To study the effect of the core radii and shell thicknesses on the LSPR property of Au@Cu 2Àx S CSNRs, we calculate the extinction spectra of Au@Cu 2Àx S CSNs with varied the core radii r 1 and the shell thicknesses Dr, as shown in Fig.…”

“… 20 Based on our present research, we found that the semiconductor shell (Cu 2− x S) is important for expanding resonance wavelength, and the RI sensitivity is greatly improved by using metal–semiconductor core–shell nanoparticles (CSNPs). 21 But the RI sensitivity can be further improved by using metal–semiconductor core–shell nanorods (CSNRs). Nevertheless, the plasmon wavelengths shift and RI sensitivity behaviors of metal–semiconductor CSNRs have not yet attracted sufficient attention.…”

Instantaneous Property Prediction and Inverse Design of Plasmonic Nanostructures Using Machine Learning: Current Applications and Future Directions

“…Adapted with permission from Ref. [14] under terms of the CC-BY-NC 3.0 Unported License. Copyright Royal Society of Chemistry (2018).…”

Directing Near-Infrared Photon Transport with Core@Shell Particles

“…21,22 The addition of a shell can enhance the radiative heat transfer between metal@oxide particles 23 or improve the sensitivity of the mode frequency to changes in the refractive index of the medium. 24 Conventional metals often require shape anisotropy to extend to the near-IR, 3,25 Further, the effectiveness of metallic particles is limited by large Ohmic dissipation at high temperatures. 26 By contrast, low-bandgap semiconductor particles exhibit large scattering in the near-IR without resorting to internal structuring or non-spherical shapes.…”