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Negative refraction in photonic crystals. Mike Kaliteevski Durham University. Outine. Photonic Crystals: Introduction Negative refraction in left-handed material Non-diffracting beams Electromagnetic wiggler. n 2. n 1. t. r. Bragg reflector. Bragg reflector. n 1. n 1. r. n 2.
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Negative refraction in photonic crystals Mike Kaliteevski Durham University
Outine Photonic Crystals: Introduction Negative refraction in left-handed material Non-diffracting beams Electromagnetic wiggler
n2 n1 t r Bragg reflector
Bragg reflector n1 n1 r n2 d2
n2 n2 n1 n1 r d2 d2 Bragg reflector Periodic sequence of the pairs of quarterwave layers is the Bragg reflector. The waves, reflected from different boundaries experience positive interference (enforce each other).
Formation of the photonic band gap in periodic structures BR BR BR = c/(n1d1+n2d2)
Microcavity Electric field Magnetic field
Plane waves method Wave equation Lattice vector Bloch theorem Reciprocal lattice vector
Plane waves method Wave equation Reciprocal lattice vector
Transmissiom of light Modelling Experiment
Defects in photonic crystals m = 1 m = 1 m = 2 m = 2 m = 0 m = 3
3D Photonic crystals OE_15_12982
Transmission of light and bandstructure in opals and inverse opals.
Right - hand materials • Usual electromagnetic word
Left - hand materials V.G.Veselago, Electrodinamics of the materials with negative dielectric and magnetic constant (1967) • Inversed Doppler effect • Inversed Vavilov – Cherenkov effect • Negative refraction
Refraction Kτ Kτ
Positive refraction Kτ Kτ
Negative refraction Kτ Kτ
Left - hand materials Negative refraction Flat Lense
Flat lence n1 n2 n1 D A n2 =-n1 L
Superlence ??? Автор ввел понятие "суперлинза", ...утверждая, что для этого устройства отсутсвует дифракционный предел. Наверное, наиболее убедительное доказательство ошибочности подобного рода утверждений можно найти в ... [ В.Г.Веселаго, УФН, 173 (7) 790 (2003) ] J. B. Pendry , Negative Refraction Makes a Perfect Lens, Phys. Rev. Lett. 85, 3966 - 3969 (2000) With a conventional lens sharpness of the image is always limited by the wavelength of light. An unconventional alternative to a lens, a slab of negative refractive index material, has the power to focus all Fourier components of a 2D image, even those that do not propagate in a radiative manner. Such “superlenses” ..... Comment: John Michael Williams, Some Problems with Negative Refraction, Phys. Rev. Lett. 87, 249703 (2001) Comment: G. W. 't Hooft, Comment on “Negative Refraction Makes a Perfect Lens”, Phys. Rev. Lett. 87, 249701 (2001) Reply: M. Nieto-Vesperinas and N. Garcia, Nieto-Vesperinas and Garcia Reply:, Phys. Rev. Lett. 91, 099702 (2003)
Realization of left-hand materials Metamaterials Photonic crystals
Negative refraction in photonic crystals vgr<0 vgr>0 2D hexagonal metallicPC, D=200microns, d = 60 microns
Refraction of wave in photonic crystal prism vgr<0 vgr>0
Experimental study of negative refraction of THzusing QCL SIGNAL WITHOUT SAMPLE Negatively refracted beam