论文标题
Helimagnets中的Skyrmion歼灭和拓扑模式的拓扑相变的临界条件
Skyrmion annihilation in helimagnets and the critical condition of topological phase transitions with a soft mode
论文作者
论文摘要
自1950年代以来，拓扑孤子已被用来描述基本颗粒[1-3]和类似粒子的场构型[4-13]，这些构型几乎出现在从亚原子到宇宙学量表[3,14-16]的物理学分支中。在这种情况下，粒子的形成和an灭对应于拓扑相变，其实际过程和机制仍然难以捉摸。在这里，我们表明，随着局部磁化磁化的逆转逆转在其中心点的启动时，helimagnets中孤立的天际腔的歼灭。在临界场上，出现了旋转波激发的软模式，它消失了局部磁化模量以及中心的软模式调节的新兴弹性刚度[17]，这使其成为新兴的磁性单极[6]。这个软点消失了逆转中心局部磁化的能量障碍，这不可避免地歼灭了天空。在此基础上，我们提出了具有软模式的场溶液拓扑相变的一般临界条件：拓扑相变于那些空间点启动，在该空间点中，软模式调节的新出现刚度矩阵损失了其正定性。
Since the 1950s, topological solitons have been used to describe elementary particles[1-3] and particle-like field configurations[4-13] that appear in almost all branches of physics ranging from subatomic to cosmological scales[3,14-16]. In this context, formation and annihilation of particles corresponds to topological phase transitions, whose actual process and mechanism remain elusive. Here, we show that annihilation of an isolated skyrmion in helimagnets as the applied magnetic field increases initiates at its center point by a local magnetization reversal. At the critical field, a soft mode of the spin-wave excitation appears, which vanishes the local magnetization modulus as well as the soft-mode-modulated emergent elastic stiffness[17] at the center, which makes it an emergent magnetic monopole[6]. This softened point vanishes the energy barrier of reversing the local magnetization at the center, which inevitably annihilates the skyrmion. On this basis, we propose a general critical condition for topological phase transitions of field solutions with a soft mode: topological phase transitions initiate at those spatial points where the soft-mode-modulated emergent stiffness matrix losses its positive-definiteness.
