Wave propagation and properties in negative index media

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Summary 

Negative index media (NIM), also known as left-handed media (LHM) or double negative media (DNG), have not been found in nature.   Artificial materials, called metamaterials, have been created to demonstrate the existence of negative refraction; i.e., a negative index of refraction.  This project studies wave propagation and other properties involved with negative index media.   In a negative index medium, the phase velocity is opposite to the direction of propagation (the Poynting vector direction).  Thus, the vector triad of electric field, magnetic field, and k vector, which is a right-handed triad in ordinary media, becomes a left-handed triad in negative index media; hence, the term left-handed media was coined by the Russian, Veselago.

Because of the left-handedness of this material, several interesting wave properties can be exploited for applications ranging from antenna design to optics, transmission lines, and sensors.  The figure below shows how the center of a beam wave packet refracts negatively in accordance with Snell’s law at the interface of free space with a NIM.  However, the shape and orientation of the ellipsoidal packet changes in a more complicated way.  The possibility of high-resolution focusing by a planar layer is another interesting property which we have explored in considerable detail.

Wave packet propagation onto the interface of free space and NIM

Related publications

• J. R. Thomas, and A. Ishimaru, "Wave Packet incident on negative index media," IEEE Transactions on Antennas and Propagation, vol. 53, no. 5, pp. 1591-1595, May 2005.
• A. Ishimaru, S. Jaruwatanadilok, and Y. Kuga, "Generalized surface plasmon resonance sensors using metameterials and negative index materials," Progress in Electromagnetics Research, vol. 51, pp. 139-152, June 27, 2005.
• A. Ishimaru, J. R. Thomas, and S. Jaruwatanadilok, "Electromagnetic waves over half-space metamaterials of arbitrary permittivity and permeability," IEEE Transactions of Antennas and Propagation, March 2005.
• J. R. Thomas, and A. Ishimaru, "Poynting Vector and Electric and Magnetic Energy Density as Focused by a Slab with Relative Permittivity and Permeability Close to –1," URSI - APS, Albuquerque, NM, July 9-14, 2006.
• J. R. Thomas, and A. Ishimaru, "Fields and Poynting vector in and near the focal plane of a slab with index of refraction close to –1 for a line source," URSI - APS, Washington, DC, July 3-8, 2005.
• A. Ishimaru, J. R. Thomas, S. Jaruwatanadilok, and Y. Kuga, "Source Excitations of Backward Lateral and Surface Waves, Surface Plasmons and Sub Wavelength Focusing in DNG Layers,"  URSI - APS, Washington, DC, July 3-8, 2005.
• A. Ishimaru,  S. Jaruwatanadilok, and Y. Kuga, "Generalized Surface Plasmon Resonance Sensor Using Metamaterials and Negative Index Medium," URSI - APS, Monterey, CA, June 20-26, 2004.
• A. Ishimaru, and J. R. Thomas, "Waves in layered negative index media excited by a space-time localized source," URSI, Piza, Italy, May 23-27, 2004.
• J. R. Thomas, and A. Ishimaru, "Transmission properties of material with relative permittivity and permeability close to -1," SPIE: Remote Senging and Space Technology, Seattle, WA, August 7-11, 2002.

Sponsored by NSF