Slowdown of the wave packages in finite slabs of periodic medias
Slowdown of the wave packages in finite slabs of periodic medias
复制标题
周期性介质有限板中波包的减速
DOI：
10.1088/0959-7174/14/3/012
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
B. Vainberg
中科院分区：
文献类型：
--
作者：
S. Molchanov;B. Vainberg
本文提供了一个简单的数学模型来描述波在周期介质的有限平板中的传播。该模型涉及近几年物理文献中广泛讨论的Crow(耦合谐振器光波导)型器件。考虑一种入射脉冲，其频率分布在奇异频率的一个小邻域内，对于该邻域，介质的色散关系非常平坦，并且群速度(对于无限大介质)很小。证明了该脉冲只有一小部分能量以光速传播。另一部分能量以群速度传播。为这种减速付出的代价是反映了入射脉冲的大部分能量。
Abstract A simple mathematical model is provided for a description of wave propagation through finite slabs of periodic media. The model concerns the devices of CROW (coupled resonators optical waveguide) type which are widely discussed in physical literature in the last several years. An incident pulse is considered, whose frequency is distributed in a small neighbourhood of a singular frequency for which the dispersion relation of the medium is very flat, and the group velocity (for the infinite medium) is small. It is proved that only a small part of the energy of the pulse propagates with the speed of light. Another part of the energy propagates with the group velocity. The price to pay for this slowdown is the reflection of the majority of the energy of the incident pulse.