Kalisky B, Myasoedov Y, Shaulov A, Tamegai T, Zeldov E, Yeshurun Y
Institute for Superconductivity, Department of Physics, Bar-Ilan University, Ramat-Gan, Israel.
Phys Rev Lett. 2007 Mar 9;98(10):107001. doi: 10.1103/PhysRevLett.98.107001. Epub 2007 Mar 6.
Magneto-optical measurements of transient vortex states in Bi2Sr2CaCu2O8+delta show enhanced effects of metastability in prism-shaped as compared to platelet crystals including a significant shift of the second magnetization peak and qualitatively different dynamics. In contrast to platelets, where dislocations are generated only at the sample edges, we propose that in prism samples the dislocations are generated dynamically in the entire sample due to distributed surface barriers. As a result, a dynamic phase transition from a Bragg glass to a metastable disordered phase may occur well below the thermodynamic transition field.
对Bi2Sr2CaCu2O8+δ中瞬态涡旋态的磁光测量表明，与片状晶体相比，棱柱状晶体中亚稳性的影响增强，包括第二磁化峰的显著位移和定性上不同的动力学。与仅在样品边缘产生位错的片状晶体不同，我们提出在棱柱状样品中，由于分布的表面势垒，位错在整个样品中动态产生。因此，从布拉格玻璃到亚稳无序相的动态相变可能在远低于热力学转变场的情况下发生。
