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Tham khảo tài liệu 'superconductivity theory and applications part 9', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Properties of Macroscopic Quantum Effects and Dynamic Natures of Electrons in Superconductors 189 condensation. As a matter of fact immediately after the first experimental observation of this condensation phenomenon it was realized that the coherent dynamics of the condensed macroscopic wave function could lead to the formation of nonlinear solitary waves. For example self-localized bright dark and vortex solitons formed by increased bright or decreased dark or vortex probability density respectively were experimentally observed particularly for the vortex solution which has the same form as the vortex lines found in type II-superconductors and superfluids. These experimental results were in concordance with the results of the above theory. In the following sections of this text we will study the soliton motions of quasiparticles in macroscopic quantum systems superconductors. We will see that the dynamic equations in macroscopic quantum systems do have such soliton solutions. 3.4 Differences of macroscopic quantum effects from the microscopic quantum effects From the above discussion we may clearly understand the nature and characteristics of macroscopic quantum systems. It would be interesting to compare the macroscopic quantum effects and microscopic quantum effects. Here we give a summary of the main differences between them. 1. Concerning the origins of these quantum effects the microscopic quantum effect is produced when microscopic particles which have only a wave feature are confined in a finite space or are constituted as matter while the macroscopic quantum effect is due to the collective motion of the microscopic particles in systems with nonlinear interaction. It occurs through second-order phase transition following the spontaneous breakdown of symmetry of the systems. 2. From the point-of-view of their characteristics the microscopic quantum effect is characterized by quantization of physical quantities such as energy momentum angular momentum etc. .
