title: Thermoplasmonic Study of a Triple Band Optical Nanoantenna Strongly Coupled to Mid IR Molecular Mode.
abstract: We report the first thermal study of a triple band plasmonic nanoantenna strongly coupled to a molecular mode at mid IR wavelength (MW IR). The hybrid plasmonic structure supports three spatially and spectrally variant resonances of which two are magnetic and one is dipolar in nature. A hybridized mode is excited by coupling the structure's plasmonic mode with the vibrational mode of PMMA at 5.79 μm. Qualitative agreement between the spectral changes in simulation and experiment clearly indicates that resistive heating is the dominant mechanisms behind the intensity changes of the dipolar and magnetic peaks. The study also unveils the thermal insensitivity of the coupled mode intensity as the temperature is increased. We propose a mechanism to reduce the relative intensity change of the coupled mode at elevated temperature by mode detuning and surface current engineering and demonstrate less than 9% intensity variation. Later, we perform a temperature cycling test and investigate into the degradation of the Au-PMMA composite device. The failure condition is identified to be primarily associated with the surface chemistry of the material interface rather than the deformation of the nanopatterns. The study reveals the robustness of the strongly coupled hybridized mode even under multiple cycling.
authors.affiliation: Department of Electrical &Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576, Singapore.|Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576.|National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Department of Micro/Nano Electronics, Shanghai Jiao Tong University, Dong Chuan Road 800, 200240 Shanghai, P. R. China.|NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Dihan
authors.initials: D
authors.lastname: Hasan
authors.affiliation: Department of Electrical &Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576, Singapore.|Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576.|NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Chong Pei
authors.initials: CP
authors.lastname: Ho
authors.affiliation: Department of Electrical &Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576, Singapore.|Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576.|NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Prakash
authors.initials: P
authors.lastname: Pitchappa
authors.affiliation: National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Department of Micro/Nano Electronics, Shanghai Jiao Tong University, Dong Chuan Road 800, 200240 Shanghai, P. R. China.
authors.forename: Bin
authors.initials: B
authors.lastname: Yang
authors.affiliation: National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Department of Micro/Nano Electronics, Shanghai Jiao Tong University, Dong Chuan Road 800, 200240 Shanghai, P. R. China.
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Yang
authors.affiliation: Department of Electrical &Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576, Singapore.|Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576.|NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Chengkuo
authors.initials: C
authors.lastname: Lee