title: Strong and highly asymmetrical optical absorption in conformal metal-semiconductor-metal grating system for plasmonic hot-electron photodetection application.
abstract: We propose an architecture of conformal metal-semiconductor-metal (MSM) device for hot-electron photodetection by asymmetrical alignment of the semiconductor barrier relative to the Fermi level of metals and strong energy localization through plasmonic resonances. Compared with the conventional grating design, the multi-layered grating system under conformal configuration is demonstrated to possess both optical and electrical advantages for high-sensitivity hot-electron photodetection. Finite-element simulation reveals that a strong and highly asymmetrical optical absorption (top metal absorption >99%) can be realized under such a conformal arrangement. An analytical probability-based electrical simulation verifies the strong unidirectional photocurrent, by taking advantage of the extremely high net absorption and a low metal/semiconductor barrier height, and predicts that the corresponding photoresponsivity can be ~3 times of that based on the conventional grating design in metal-insulator-metal (MIM) configuration.
authors.affiliation: College of Physics, Optoelectronics and Energy &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.|Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province &Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Wu
authors.affiliation: College of Physics, Optoelectronics and Energy &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.|Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province &Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006, China.
authors.forename: Yaohui
authors.initials: Y
authors.lastname: Zhan
authors.affiliation: College of Physics, Optoelectronics and Energy &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.|Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province &Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhang
authors.affiliation: College of Physics, Optoelectronics and Energy &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.|Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province &Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006, China.
authors.forename: Shaolong
authors.initials: S
authors.lastname: Wu
authors.affiliation: College of Physics, Optoelectronics and Energy &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.|Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province &Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Li