Novel Chiral Metamaterials

About

Background Chiral metamaterials (CMTM), especially double-negative (DNG) metamaterials have received much attention in recent years due to their numerous potential applications in various industrial uses including making antireflection coatings, microwave and optoelectronic technologies, chemical applications and biomedical imaging [1].  CMTM can provide more accurate identification of the correct isomer of new drugs. Since incorrect isomers results in unwanted patient side effects, this would ensure only correct chirality drugs are administered to patients for a given medical condition. Current optical instrumentation for making measurements for high throughput, high information content screening of chemical compounds to select specific  drugs for further development possess severe limitations. Using novel CMTMs would uniquely overcome this information limitation, thus enabling collection of much higher information content from drug screening tests. However, for drug testing and biomedical imaging, CMTM’s need to be tunable and cost-effective. Technology UMass Lowell Professor, Alkim Akyurtlu and her colleagues, have designed novel chiral metamaterials that have simultaneously negative effective electric permittivity and negative effective magnetic permeability in a given frequency region [2]. The metamaterials design methodology is novel and the rotation dependence of the Y structure is judged to be completely novel and potentially of great utility in device creation. This structure is novel and shows very low loss and ease in tunability of the frequency at which the negative index of refraction as well as chirality occurs. This is the first time fabrication efforts have been made on a negative index of refraction chiral material in the terahertz regime. This work represents the first of its kind in experimental validations of the negative index of refraction in chiral metamaterials in the microwave terahertz regime. The wedge simulations and experiments in the microwave regime also show the property of beam splitting into two different angular paths, a property having great utility in optical operations.  Applications Drug Discovery Biomedical Imaging Design of microwave transmission lines, antennas, mode conversion devices, directional couplers and lenses  Antireflection coatings, microwave and optoelectronic technologies, chemical applications Advantages Low Cost Compact and Portable Increased Sensitivity in the Microwave Regime References [1] Eleftheriades, George V.; Balmain, Keith G. (2005). Negative-refraction metamaterials: fundamental principles and applications. Wiley, John & Sons. p. 340 [2] Wongkasem, N., Akyurtlu, A., Marx, K.A., Dong, Q., Li, J., and Goodhue, W.D. (2007) “Development of Chiral Negative Refractive Index Metamaterials for the Terahertz Frequency Range”, IEEE Transactions of Antennas and Propagation, V55, No. 11, pp3052-3062, November 2007