Lossless Phase Change Materials for Adjustable Tamm Plasmon Polaritons in the Near‐Infrared

Abstract Incorporation of phase‐change materials (PCM) into nanophotonic structures is a straightforward method for making them tunable. The binary semiconducting chalcogenide antimony trisulfide (Sb 2 S 3 ) is a suitable PCM for nanophotonic applications in the near‐infrared (NIR) owing to its high refractive index, low optical losses, and wide bandgap. Therefore, in this study, Sb 2 S 3 Tamm plasmon polaritons (TPPs) are fabricated with a focus on their widespread use in nanophotonic applications. For this, a gold film and Sb 2 S 3 are deposited on the distributed Bragg reflector through e‐beam evaporation. TPPs are excited at the interface between the distributed Bragg reflector (DBR) and the metal layer. The refractive index, extinction coefficient, and high‐Q reflectance spectra of the developed Sb 2 S 3 are measured and analyzed. The Sb 2 S 3 TPPs exhibit a resonance shift of 45 nm caused by the phase change of Sb 2 S 3 from amorphous to crystalline. In addition, the angle‐dependent resonance shifts of 85, 76, and 63 nm are achieved by unpolarized, transverse magnetic (TM), and transverse electric (TE) modes near NIR light, respectively. The developed Sb 2 S 3 TPP can be applied in various nanophotonics applications, including optical memory, optical data storage, and LiDAR receiver systems.