Mishra Prabhat, Debnath Anil K, Dutta Choudhury Sharmistha
Materials Processing & Corrosion Engineering Division, Bhabha Atomic Research Centre, Mumbai 400 085, India.
Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, India.
Phys Chem Chem Phys. 2022 Mar 9;24(10):6256-6265. doi: 10.1039/d1cp05822c.
The development of alternative plasmonic materials that can replace gold and silver is of long-standing interest in materials research. In this study, we have prepared and characterized thin films of TiN, an emerging plasmonic material, and examined its effectiveness for fluorescence coupling in metal-dielectric structures having TiN as the plasmonically active component. We have used a combination of experiment and reflectivity calculations to determine the nature and dispersion of the optical modes sustained by the metal-dielectric structures, which furthermore are adjustable by varying the thickness of the dielectric layer. Our results reveal that fluorophores placed on the TiN substrates can couple with the surface-plasmon mode and/or the waveguide modes supported by these structures, to provide polarized and directional emission over narrow angular ranges. The performance of TiN substrates for surface plasmon-coupled emission (SPCE) and waveguide-coupled emission (WGCE) is found to be comparable with conventional Au substrates. Importantly, the TiN thin films are reusable, which is certainly advantageous for their use in SPCE or WGCE-based fluorescence sensing applications.
开发能够替代金和银的新型等离子体材料一直是材料研究领域长期关注的课题。在本研究中，我们制备并表征了一种新兴的等离子体材料——氮化钛薄膜，并研究了其在以氮化钛作为等离子体活性成分的金属 - 电介质结构中用于荧光耦合的有效性。我们结合实验和反射率计算来确定金属 - 电介质结构所支持的光学模式的性质和色散，而且这些模式可通过改变电介质层的厚度进行调节。我们的结果表明，放置在氮化钛基底上的荧光团能够与这些结构所支持的表面等离子体模式和/或波导模式耦合，从而在窄角度范围内提供偏振和定向发射。结果发现，氮化钛基底用于表面等离子体耦合发射（SPCE）和波导耦合发射（WGCE）的性能与传统金基底相当。重要的是，氮化钛薄膜可重复使用，这对于其在基于SPCE或WGCE的荧光传感应用中的使用无疑是有利的。
