title: Unidirectional invisibility induced by parity-time symmetric circuit.
abstract: Parity-time (PT) symmetric structures present the unidirectional invisibility at the spontaneous PT-symmetry breaking point. In this paper, we propose a PT-symmetric circuit consisting of a resistor and a microwave tunnel diode (TD) which represent the attenuation and amplification, respectively. Based on the scattering matrix method, the circuit can exhibit an ideal unidirectional performance at the spontaneous PT-symmetry breaking point by tuning the transmission lines between the lumped elements. Additionally, the resistance of the reactance component can alter the bandwidth of the unidirectional invisibility flexibly. Furthermore, the electromagnetic simulation for the proposed circuit validates the unidirectional invisibility and the synchronization with the input energy well. Our work not only provides an unidirectional invisible circuit based on PT-symmetry, but also proposes a potential solution for the extremely selective filter or cloaking applications.
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Lv
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Jiahui
authors.initials: J
authors.lastname: Fu
authors.affiliation: School of Electronic Engineering, Xidian University, Xi'an, 710071, China.
authors.forename: Bian
authors.initials: B
authors.lastname: Wu
authors.affiliation: College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Rujiang
authors.initials: R
authors.lastname: Li
authors.affiliation: Propagation Group, Wireless Technologies Branch, Communications Research Centre Canada, Government of Canada, 3701 Carling Ave., Box 11490, Station H, Ottawa, Ontario K2H 8S2, Canada.
authors.forename: Qingsheng
authors.initials: Q
authors.lastname: Zeng
authors.affiliation: Harbin medical university, No. 157, Baojian Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Yin
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Propagation Group, Wireless Technologies Branch, Communications Research Centre Canada, Government of Canada, 3701 Carling Ave., Box 11490, Station H, Ottawa, Ontario K2H 8S2, Canada.
authors.forename: Lei
authors.initials: L
authors.lastname: Gao
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Wan
authors.initials: W
authors.lastname: Chen
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Zhefei
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Liang
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Ao
authors.initials: A
authors.lastname: Li
authors.affiliation: Microwave and Electromagnetic Laboratory, Harbin Institute of Technology, No. 92, Xidazhi Street, Nangang District, Harbin City, Heilongjiang Province, China.
authors.forename: Ruyu
authors.initials: R
authors.lastname: Ma