Nosenko V, Goree J, Ma Z W, Piel A
Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242, USA.
Phys Rev Lett. 2002 Apr 1;88(13):135001. doi: 10.1103/PhysRevLett.88.135001. Epub 2002 Mar 15.
Mach cones composed of shear waves were observed experimentally in a two-dimensional screened-Coulomb crystal. Highly charged microspheres suspended in a plasma and interacting with a repulsive Yukawa potential arranged themselves in a triangular lattice with hexagonal symmetry. Mach cones were excited by applying a force from the radiation pressure of a moving laser beam. They had a single-cone structure, which is explained by the almost dispersionless character of shear waves. The cone's opening angle obeyed the Mach-cone-angle relation. Results are compared to a molecular-dynamics simulation.
在二维屏蔽库仑晶体中通过实验观察到了由剪切波构成的马赫锥。悬浮在等离子体中并与排斥性 Yukawa 势相互作用的高电荷微球排列成具有六边形对称性的三角晶格。通过施加来自移动激光束辐射压力的力来激发马赫锥。它们具有单锥结构，这可以用剪切波几乎无色散的特性来解释。锥的开口角符合马赫锥角关系。将结果与分子动力学模拟进行了比较。
