Moreover, in their work the determination of the effective parameters relies on numerically simulated results and each simulation provides the parameters for only one boundary. μ r( r) = μ r( r + R lmn and ε r = ε r ( r + R), where R lmn represents a unit lattice translation vector. In fact, these two parameters in a PhC are known and accurately given as periodic functions, i.e. Second, negative-refraction PhCs work by the unique photonic dispersion, which however does not provide any clue for negative permittivity and negative permeability. If they only describe the surface properties of the PhC, then the effective parameters inside the PhC are still unknown. First, effective permittivity and permeability as bulk parameters for material should not depend on the boundary. Their work provides a very novel approach to calculate effective impedance, but several issues are still open to discuss. In their work, they assumed that the relations among effective permittivity, permeability, impedance, and refractive index, η eff = μ eff ε eff and n eff = μ eff ε eff, are still valid. More recently, Decoopman, et al., proposed to calculate the impedance of a negative-refraction PhC by observing the reflection into its matched medium, and numerically demonstrated that the value of the impedance of a PhC strongly depends on its boundary - especially the way of truncation of the elementary cells located on this boundary. Although significant experimental progress has been made in observing and employing this novel phenomenon, several basic questions are still unclear - for example, what is the relation between metamaterial and negative-refraction PhCs, and specifically whether negative-refraction PhCs have negative effective permittivity and negative permeability.
#Quantumwise calculation of permittivity full#
Subsequently, we experimentally achieved subwavelength imaging by a 3D PhC flat lens exhibiting full 3D negative refraction. Meanwhile, negative refraction and imaging by negative refraction were also demonstrated using 2D photonic crystals (PhCs) by dispersion-engineering. Recently, the work on metamaterial and “perfect lenses” revived Veselago’s lefthanded materials and triggered intensive discussion on negative refraction. The unique power propagation mechanism in the photonic crystal is demonstrated through time-evolution of eigen-fields. The value of the surface impedance is shown to be location-dependent and is validated by finite-difference time-domain simulations. Effective permittivity, permeability, and surface impedance are calculated by averaging the eigen-fields. We consider the eigen-fields of a two-dimensional negative-refraction photonic crystal and obtain negative effective permittivity and negative effective permeability. Note: Author names will be searched in the keywords field, also, but that may find papers where the person is mentioned, rather than papers they authored.Use a comma to separate multiple people: J Smith, RL Jones, Macarthur.Use these formats for best results: Smith or J Smith.For best results, use the separate Authors field to search for author names.Use quotation marks " " around specific phrases where you want the entire phrase only.Question mark (?) - Example: "gr?y" retrieves documents containing "grey" or "gray".Asterisk ( * ) - Example: "elect*" retrieves documents containing "electron," "electronic," and "electricity".Improve efficiency in your search by using wildcards.Example: (photons AND downconversion) - pump.Example: (diode OR solid-state) AND laser.Note the Boolean sign must be in upper-case. Separate search groups with parentheses and Booleans.
Keep it simple - don't use too many different parameters.
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