title: A naked eye refractive index sensor with a visible multiple peak metamaterial absorber.
abstract: We report a naked eye refractive index sensor with a visible metamaterial absorber. The visible metamaterial absorber consisting of a silver dendritic/dielectric/metal structure shows multiple absorption peaks. By incorporating a gain material (rhodamine B) into the dielectric layer, the maximal magnitude of the absorption peak can be improved by about 30%. As the metamaterial absorber is sensitive to the refractive index of glucose solutions, it can function as a sensor that quickly responds to variations of the refractive index of the liquid. Meanwhile, since the response is presented via color changes, it can be clearly observed by the naked eyes. Further experiments have confirmed that the sensor can be used repeatedly.
authors.affiliation: Smart Materials Laboratory, Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710129, China. marcos12@126.com.
authors.forename: Heli
authors.initials: H
authors.lastname: Ma
authors.affiliation: Smart Materials Laboratory, Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710129, China. songkun@mail.nwpu.edu.cn.
authors.forename: Kun
authors.initials: K
authors.lastname: Song
authors.affiliation: Smart Materials Laboratory, Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710129, China. mzlmql@126.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Smart Materials Laboratory, Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710129, China. xpzhao@nwpu.edu.cn.
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Zhao
references.citation: Nature. 2007 Nov 15;450(7168):397-401
references.pmid: 18004380
references.citation: Nature. 2010 Aug 5;466(7307):735-8
references.pmid: 20686570
references.citation: Phys Rev Lett. 2010 May 21;104(20):207403
references.pmid: 20867064
references.citation: Nano Lett. 2012 Mar 14;12(3):1443-7
references.pmid: 22309161
references.citation: Sensors (Basel). 2010;10(3):2348-58
references.pmid: 22294930
references.citation: Science. 2006 Nov 10;314(5801):977-80
references.pmid: 17053110
references.citation: Phys Rev Lett. 2000 Oct 30;85(18):3966-9
references.pmid: 11041972
references.citation: Opt Lett. 2011 Mar 15;36(6):945-7
references.pmid: 21403737
references.citation: Phys Rev Lett. 2008 May 23;100(20):207402
references.pmid: 18518577
references.citation: Opt Express. 2011 Jun 20;19(13):12688-99
references.pmid: 21716512
references.citation: Opt Lett. 2011 Apr 15;36(8):1524-6
references.pmid: 21499411
references.citation: Nano Lett. 2010 Jul 14;10(7):2342-8
references.pmid: 20560590