Wang Xiaosheng, Chen Zhigang, Wang Jiandong, Yang Jianke
Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132, USA.
Phys Rev Lett. 2007 Dec 14;99(24):243901. doi: 10.1103/PhysRevLett.99.243901.
We report the first experimental and theoretical demonstrations of in-band (or embedded) lattice solitons. Such solitons appear in trains, and their propagation constants reside inside the first Bloch band of a square lattice, different from all previously observed solitons. We show that these solitons bifurcate from Bloch modes at the interior high-symmetry X points within the first band, where normal and anomalous diffractions coexist along two orthogonal directions. At high powers, the in-band soliton can move into the first band gap and turn into a gap soliton.
我们报道了带内（或嵌入式）晶格孤子的首次实验和理论证明。此类孤子以序列形式出现，其传播常数位于方形晶格的第一布洛赫带内，这与之前观测到的所有孤子均不同。我们表明，这些孤子在第一带内的内部高对称X点处从布洛赫模式分叉而来，在该点处，正常衍射和反常衍射沿两个正交方向共存。在高功率下，带内孤子可移入第一带隙并转变为带隙孤子。
