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Colloidal Synthesis of Nanopatch Antennas for Applications in Plasmonics and Nanophotonics
Published on: May 28, 2016
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Refractory plasmonics: orientation-dependent plasmonic coupling in TiN and ZrN nanocubes
Ahmed H El-Saeed1, Nageh K Allam
1Energy Materials Laboratory (EML), School of Sciences and Engineering, The American University in Cairo, New Cairo 11835, Egypt. nageh.allam@aucegypt.edu.
Physical Chemistry Chemical Physics : PCCP
|January 4, 2018
Summary
Transition metal nitrides like TiN and ZrN show promise as plasmonic materials. Their localized surface plasmon resonance (LSPR) coupling intensifies as nanocubes get closer, creating "hot spots" for various applications.
Area of Science:
- Materials Science
- Nanotechnology
- Plasmonics
Background:
- Noble metals (Ag, Au) dominate plasmonics, but cost and stability are concerns.
- Transition metal nitrides (TMNs), particularly TiN and ZrN, offer potential alternatives due to their refractory nature and tunable plasmonic properties.
Purpose of the Study:
- To investigate the localized surface plasmon resonance (LSPR) coupling in transition metal nitride nanocubes.
- To explore the influence of separation distance and orientation on plasmon coupling.
- To compare the plasmonic performance of TMNs with traditional noble metals.
Main Methods:
- Finite-difference time-domain (FDTD) simulations were employed to calculate optical properties.
- Extinction, absorption, and scattering cross-sections were computed for TiN nanocube pairs.
- Electric field intensity modes and plasmon ruler equations were derived for various configurations.
Main Results:
- Plasmon coupling increased significantly with decreasing separation distance between nanocubes.
- Ag-Ag pairs exhibited the highest electric field intensity, followed by Au-Au and ZrN-ZrN.
- A red-shift in LSPR peak wavelength was observed as separation distance decreased.
- The critical separation distance for TiN nanocubes to mimic isolated nanocube LSPR was identified.
Conclusions:
- Transition metal nitrides, especially TiN and ZrN, are viable plasmonic materials with tunable coupling.
- The identified
- hot spot
- regions are crucial for applications in sensing, catalysis, and nanomedicine.
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