Magnetoplasmonic sensors are attractive candidates for ultrasensitive chemical and biomedical sensor applications.A variety of ferromagnetic metal thin films have been used for magnetoplasmonic device applications, ye...Magnetoplasmonic sensors are attractive candidates for ultrasensitive chemical and biomedical sensor applications.A variety of ferromagnetic metal thin films have been used for magnetoplasmonic device applications, yet the dependence of sensor performance on the optical and magneto-optical properties of ferromagnetic metal materials has been rarely studied. In this work, we report the study of enhanced magneto-optical Kerr effect(MOKE) and sensing performance in Au∕Fe_xCo_(1-x)bilayer magneto-optical surface plasmon resonance(MOSPR) transducers.The optical constants of Fe_xCo_(1-x)(x = 0, 0.29, 0.47, 0.65, and 1) in a sputter-deposited Au∕Fe_xCo_(1-x)device are characterized by the attenuated total internal reflection(ATR) method. Fe_xCo_(1-x)thin films show different MOKEs as a function of the chemical concentration, with the highest transverse MOKE signal observed in Fe_0.7Co_0.3.Index sensing performance is closely related to the material's optical and magneto-optical constants. By studying the sensing performance in the parameter space of the Au∕Fe_xCo_(1-x)bilayer thicknesses, the highest sensitivity is found to be 0.385(theoretical) and 0.306 RIU^(-1)(experimental) in the Au∕Fe_0.7Co_0.3 MOSPR devices. Our research highlights the influence of the optical properties of ferromagnetic material to device sensitivity in MOSPR transducers. The high sensitivity in Au∕Fe_xCo_(1-x)MOSPR devices make these structures attractivecandidates for chemical and biomedical sensing applications.展开更多
基金Ministry of Science and Technology of the People’s Republic of China(MOST)(2016YFA0300802)National Natural Science Foundation of China(NSFC)(51522204,61475031)+4 种基金Fundamental Research Funds for the Central Universities(ZYGX2014Z001)Science Foundation for Youths of Sichuan Province(2015JQO014)Doctoral Fund of Ministry of Education of China(20130185120009)Open Foundation of Key Laboratory ofMultispectral Absorbing Materials and Structures,Ministry of Education(ZYGX2013K007-5)Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT)
文摘Magnetoplasmonic sensors are attractive candidates for ultrasensitive chemical and biomedical sensor applications.A variety of ferromagnetic metal thin films have been used for magnetoplasmonic device applications, yet the dependence of sensor performance on the optical and magneto-optical properties of ferromagnetic metal materials has been rarely studied. In this work, we report the study of enhanced magneto-optical Kerr effect(MOKE) and sensing performance in Au∕Fe_xCo_(1-x)bilayer magneto-optical surface plasmon resonance(MOSPR) transducers.The optical constants of Fe_xCo_(1-x)(x = 0, 0.29, 0.47, 0.65, and 1) in a sputter-deposited Au∕Fe_xCo_(1-x)device are characterized by the attenuated total internal reflection(ATR) method. Fe_xCo_(1-x)thin films show different MOKEs as a function of the chemical concentration, with the highest transverse MOKE signal observed in Fe_0.7Co_0.3.Index sensing performance is closely related to the material's optical and magneto-optical constants. By studying the sensing performance in the parameter space of the Au∕Fe_xCo_(1-x)bilayer thicknesses, the highest sensitivity is found to be 0.385(theoretical) and 0.306 RIU^(-1)(experimental) in the Au∕Fe_0.7Co_0.3 MOSPR devices. Our research highlights the influence of the optical properties of ferromagnetic material to device sensitivity in MOSPR transducers. The high sensitivity in Au∕Fe_xCo_(1-x)MOSPR devices make these structures attractivecandidates for chemical and biomedical sensing applications.
