Application of Tamm Plasmon Polaritons and Cavity Modes for Biosensing in the Combined Spectroscopic Ellipsometry and Quartz Crystal Microbalance Method

Low-cost 1D plasmonic photonic structures supporting Tamm plasmon polaritons and cavity modes were employed for optical signal enhancement, modifying the commercially available quartz crystal microbalance with dissipation (QCM-D) sensor chip in a combinatorial spectroscopic ellipsometry and quartz microbalance method. The Tamm plasmon optical state and cavity mode (CM) for the modified mQCM-D sample obtained sensitivity of ellipsometric parameters to RIU of psi(TPP) = 126.78 RIU-1 and Delta(TPP) = 325 RIU-1, and psi(CM) = 264 RIU-1 and Delta(CM) = 645 RIU-1, respectively. This study shows that Tamm plasmon and cavity modes exhibit about 23 and 49 times better performance of ellipsometric parameters, respectively, for refractive index sensing than standard spectroscopic ellipsometry on a QCM-D sensor chip. It should be noted that for the optical biosensing signal readout, the sensitivity of Tamm plasmon polaritons and cavity modes are comparable with and higher than the standard QCM-D sensor chip. The different origin of Tamm plasmon polaritons (TPP) and cavity mode (CM) provides further advances and can determine whether the surface (TPP) or bulk process (CM) is dominating. The dispersion relation feature of TPP, namely the direct excitation without an additional coupler, allows the possibility to enhance the optical signal on the sensing surface. To the best of our knowledge, this is the first study and application of the TPP and CM in the combinatorial SE-QCM-D method for the enhanced readout of ellipsometric parameters.

Automated summary

Low-cost 1D plasmonic photonic structures were used to enhance the optical signal of a modified quartz crystal microbalance with dissipation (QCM-D) sensor chip, achieving significant improvements in refractive index sensitivity compared to standard spectroscopic ellipsometry. The sensitivity of Tamm plasmon polaritons and cavity modes in optical biosensing signal readout is comparable to or even higher than that of the standard QCM-D sensor chip. The different origins of Tamm plasmon polaritons (TPP) and cavity mode (CM) offer further advantages in determining the dominating process on the sensing surface.