Optical Chirality Enhancement in Twisted Arrays of Plasmonic Nano-rods

Document Type : Research Article


1 Assistant Professor, Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran.

2 Faculty Member, Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, TX 78712 USA.

3 Associate Professor, Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, TX 78712 USA.


An important property of electromagnetic fields, which arises from the interaction between fields and chiral molecules, is called optical chirality. By enhancing this field property, while maintaining constant input power, we are able to increase absorption of circularly polarized light by chiral molecules of a certain handedness. This enhancement is achieved through the use of achiral plasmonic nano-particles in conjunction with the twisted metamaterials. Optical chirality enhancement (OCE) has an important application in sensing enantiomers of chiral molecules. Here, we present a preliminary scheme to measure enantiomeric excess in mixtures of chiral molecules using OCE boosted by twisted metamaterials. This scheme does not require measurement of a frequency shift in the circular dichroism response.


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