Negative Index Material

A negative index will occur whenever Re + 0 (or Re n 0 for a wave propagating in the -z direction). From Equation (7.13), one can see that a sufficient (but not necessary) condition to achieve this is to have e 0 and p 0. But even if the real part of the permittivity or the permeability is positive, Re + may still be negative if 

As an example, consider a material with positive real relative permeability p. Condition (7.14) above still holds as long as 

Normal Modes, Power Flow, and Propagation Vectors in a Lossless Isotropic Medium 

Consider again a monochromatic plane wave of freqnency co with electric and magnetic wave vectors E and H, respectively  

Eliminating E ox H from these equations will yield decoupled equations for H and E  

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Physics of Negative Refraction and Negative Index Materials... 

J. Li, L. Zhou, C. Chan, P. Sheng, Photonic band gap from a stack of positive and negative index materials. Phys. Rev. Lett. 90(8), 083901 (2003)... 

Khoo,l.C., YanaWiUiams,AndresDiaz,KanChen,J.Bossard,D. Werner,E.Graugnard, and C. J. Summers. Forthcoming. Liquid-crystals for optical filters, switches and tunable negative index material development. Mol. Cryst. Liq. Cryst... 

S. A. Cummer, Perfectly matched layer behavior in negative refractive index materials, IEEE Antennas Wireless Propag. Lett, vol. 3, no. 1, pp. 172-175, 2004. 

Apart from SNOM (or NSOM), two new, highly resolving techniques are emerging that deserve brief mention here. These are stimulated emission depletion (STED) using focal and doughnut-focal beam shapes, and the microscopy with super lenses out of negative index of refraction materials (NIMs). 

In the theoretically analyzed NIM technique, objects are imaged with a resolution much smaller than the illuminating wavelength, because NIMs, unlike conventional materials, make light to refract inward rather than outward, due to the negative index of refraction." Flat nanolenses of this kind can be used as light couplers in nanooptics. This does, however, not signify a behavior of the surface material, but is rather a particular super lens effects. Practical applications are to be expected. 

NIM Negative index of refraction material used for the construction of superlenses. 

Fig. 3.11 The indicatrix of uniaxial birefringent materials, positive and negative. Positive materials have one principal refractive index greater than the other two. The optic axis is the axis of synunetry of the ellipsoid.

S.A. Ramakrishna, T.M. Grzegorczyk, Physics and Applications of Negative Refractive Index Materials (SPIE Press Bellingham, WA CRC Press, Taylor Francis Group, Boca Raton, 2009)... 

Z. Liu, J. Xu, Z. Lin, Omnidirectional reflection fiom a slab of uniaxially anisotropic negative refractive index materials. Opt. Common. 240(1), 19-27 (2004)... 

R.B. Greegor, C.G. Parazzoli, K. Li, and M.H. Tanielian, Origin of dissipative losses in negative index of refraction materials. Applied Physics Letters, Vol. 82, pp. 2356-2358,2003. 

The dielectric constant is a measure of the ease with which charged species in a material can be displaced to form dipoles. There are four primary mechanisms of polarization in glasses (13) electronic, atomic, orientational, and interfacial polarization. Electronic polarization arises from the displacement of electron clouds and is important at optical (ultraviolet) frequencies. At optical frequencies, the dielectric constant of a glass is related to the refractive index k =. Atomic polarization occurs at infrared frequencies and involves the displacement of positive and negative ions. 

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