Edge Rotational Magnons in Magnonic Crystals

It is predicted that in 2D magnonic crystals the edge rotational magnons of forward vol-ume magnetostatic spin waves can exist. Under certain conditions locally bounded magnons may ap-pear within the crystal consisting of the ferromagnetic matrix and periodically inserted magnetic/non-magnetic inclusions. It is also shown that interplay of different resonances in 2D magnonic crystalmay provide conditions for spin wave modes existence with negative group velocity.

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Negative Group Velocity of Surface Polaritons in Metal Foil Nanostructure

Journal of Nano- and Electronic Physics ◽

10.21272/jnep.9(3).03039 ◽

2017 ◽

Vol 9 (3) ◽

pp. 03039-1-03039-4 ◽

Cited By ~ 3

Author(s):

Y. M. Aleksandrov ◽

◽

V. V. Yatsishen ◽

Keyword(s):

Group Velocity ◽

Metal Foil ◽

Negative Group ◽

Surface Polaritons ◽

Negative Group Velocity

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X-wave bullets with negative group velocity in vacuum

Optics Letters ◽

10.1364/ol.31.003532 ◽

2006 ◽

Vol 31 (23) ◽

pp. 3532 ◽

Cited By ~ 17

Author(s):

Carlos J. Zapata-Rodríguez ◽

Miguel A. Porras

Keyword(s):

Group Velocity ◽

Negative Group ◽

Negative Group Velocity

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Negative Group Velocity in the Absence of Absorption Resonance

Scientific Reports ◽

10.1038/srep01628 ◽

2013 ◽

Vol 3 (1) ◽

Cited By ~ 14

Author(s):

Dexin Ye ◽

Guoan Zheng ◽

Jingyu Wang ◽

Zhiyu Wang ◽

Shan Qiao ◽

...

Keyword(s):

Group Velocity ◽

Negative Group ◽

Absorption Resonance ◽

Negative Group Velocity

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Split-ring resonator-loaded X-band waveguide supporting negative group velocity

Negative Group Delay Devices: From concepts to applications ◽

10.1049/pbcs043e_ch10 ◽

2018 ◽

pp. 291-308

Author(s):

Joaquim J. Barroso ◽

Joaquim P. Leite ◽

Pedro J. Castro ◽

Ugur C. Hasar ◽

Jose Edimar B. Oliveira

Keyword(s):

Group Velocity ◽

Ring Resonator ◽

Split Ring Resonator ◽

Negative Group ◽

Split Ring ◽

X Band ◽

Negative Group Velocity

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Study of Abnormal Group Velocities in Flexural Metamaterials

Scientific Reports ◽

10.1038/s41598-019-50146-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Hong Woo Park ◽

Joo Hwan Oh

Keyword(s):

Group Velocity ◽

Periodic Structure ◽

Three Dimensional ◽

Wave Dispersion ◽

Abnormal Behavior ◽

Flexural Wave ◽

Negative Group ◽

One Dimensional ◽

Optical Branch ◽

Negative Group Velocity

Abstract Generally, it has been known that the optical branch of a simple one-dimensional periodic structure has a negative group velocity at the first Brillouin zone due to the band-folding effect. However, the optical branch of the flexural wave in one-dimensional periodic structure doesn’t always have negative group velocity. The problem is that the condition whether the group velocity of the flexural optical branch is negative, positive or positive-negative has not been studied yet. In consequence, who try to achieve negative group velocity has suffered from trial-error process without an analytic guideline. In this paper, the analytic investigation for this abnormal behavior is carried out. In particular, we discovered that the group velocity of the optical branch in flexural metamaterials is determined by a simple condition expressed in terms of a stiffness ratio and inertia ratio of the metamaterial. To derive the analytic condition, an extended mass-spring system is used to calculate the wave dispersion relationship in flexural metamaterials. For the validation, various numerical simulations are carried out, including a dispersion curve calculation and three-dimensional wave simulation. The results studied in this paper are expected to provide new guidelines in designing flexural metamaterials to have desired wave dispersion curves.

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