Parallel Pumping of the Brillouin-Zone-Boundary Magnons in a Two-Dimensional Ferromagnet K2CuF4

The condition for the formation of Dirac cones at arbitrary points in the Brillouin zone by the accidental degeneracy of two photonic bands was examined by the degenerate perturbation theory and group theory based on the spatial symmetry of two modes. The analysis was applied to a two-dimensional square-lattice photonic crystal with C4v symmetry and the dispersion relation in the vicinity of the M point was examined. Exact agreement between the analytical and numerical calculation was obtained.

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A method for estimating the location of energy minima near the Brillouin zone boundary and its application to Gallium arsenide

Physics Letters A ◽

10.1016/0375-9601(69)90224-2 ◽

1969 ◽

Vol 29 (11) ◽

pp. 716-717 ◽

Cited By ~ 6

Author(s):

T.K. Gaylord ◽

T.A. Rabson

Keyword(s):

Gallium Arsenide ◽

Brillouin Zone ◽

Zone Boundary ◽

Brillouin Zone Boundary

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Nonlinear nonstationary equation of interaction between an electron beam and electromagnetic field near the Brillouin zone boundary

Radiophysics and Quantum Electronics ◽

10.1007/bf01039225 ◽

1984 ◽

Vol 27 (12) ◽

pp. 1099-1105 ◽

Cited By ~ 11

Author(s):

A. P. Kuznetsov ◽

S. P. Kuznetsov

Keyword(s):

Electromagnetic Field ◽

Electron Beam ◽

Brillouin Zone ◽

Zone Boundary ◽

Brillouin Zone Boundary ◽

Nonstationary Equation ◽

Nonlinear Nonstationary Equation

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Angular control of acoustic waves oblique incidence by phononic crystals based on Dirac cones at the Brillouin zone boundary

Physics Letters A ◽

10.1016/j.physleta.2017.12.014 ◽

2018 ◽

Vol 382 (6) ◽

pp. 423-427 ◽

Cited By ~ 2

Author(s):

Wen-Qiang Zhang ◽

Xin Zhang ◽

Fu-Gen Wu ◽

Yuan-Wei Yao ◽

Shui-Fang Lu ◽

...

Keyword(s):

Brillouin Zone ◽

Acoustic Waves ◽

Oblique Incidence ◽

Phononic Crystals ◽

Zone Boundary ◽

Brillouin Zone Boundary

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Photonic Band Structure of Nanochannel Glass Materials

MRS Proceedings ◽

10.1557/proc-431-449 ◽

1996 ◽

Vol 431 ◽

Author(s):

A. Rosenberg ◽

R. J. Tonucci ◽

H.-B. Lin

Keyword(s):

Band Structure ◽

Brillouin Zone ◽

Near Infrared ◽

Nearest Neighbor ◽

Dielectric Structure ◽

Zone Boundary ◽

Photonic Band Structure ◽

Brillouin Zone Boundary ◽

Photonic Band ◽

Good Agreement

AbstractWe demonstrate that nanochannel glass (NCG) materials are ideal for investigating twodimensional (2D) photonic band-structure effects. The NCG materials we have studied consist of triangular arrays of glass cylinders embedded in a glass matrix, having center-tocenter nearest-neighbor separations from 0.54 to 1.08 μm. The indices of refraction of the two glasses differ by less than 0.02 in the relevant spectral region. Narrow attenuation features occur whenever the dispersion relation for light propagating within such a periodic dielectric structure crosses a Brillouin zone boundary. The attenuations corresponding to the first Brillouin zone appear in the near-infrared (IR), at wavelengths between 1 and 3 μm, in good agreement with calculations.

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Tilt and acoustic instabilities in ABX 4, A 2 BX 4 and ABX 3 perovskite structure types: their role in the incommensurate phases of the organic–inorganic perovskites

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768105028879 ◽

2005 ◽

Vol 61 (6) ◽

pp. 616-626 ◽

Cited By ~ 18

Author(s):

Ian Peter Swainson

Keyword(s):

Brillouin Zone ◽

Three Dimensional ◽

Low Frequency ◽

Zone Boundary ◽

Brillouin Zone Boundary ◽

Perovskite Layer ◽

Modulated Phases ◽

Acoustic Instabilities ◽

Incommensurate Phases ◽

Zero Frequency

An examination of the tilt modes and other low-frequency modes is made for an isolated, untilted perovskite layer, which maps very simply to the ABX 4 perovskites. A sheet of pure tilts exists at the Brillouin Zone boundary at {ξ, ½, ζ}. An instability is also found at all wavevectors which can be described as continuously varying from pure tilts to pure layer displacements as a function of the wavevector. Analysis is extended by considering the stacking of layers in the I-centered A 2 BX 4-layer perovskites. The effect of freezing in the commensurate tilt required to generate the Cmca tilt system, pertinent to the modulated phases of propylammonium salts, is examined. The zero-frequency modes are restricted to two planes in the Brillouin Zone. All of the observed wavevectors associated with modulated phases, and the commensurately tilted propylammonium tetrachlorocadmate, are consistent with this calculation. The effect of full three-dimensional connectivity is briefly reviewed for the true ABX 3 perovskites. While pure tilt incommensurates appear to be hypothetically possible, they do not appear to have been observed to date.

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