We discuss two possible mechanisms of the flux flow instability (FFI) in type II superconducting strips. While the nature of nonequilibrium effects leading to this instability is widely accepted (Joule heating and finite relaxation time of the superconducting order parameter) still there is a question how FFI develops in space. According to one scenario instability occurs simultaneously in the whole sample and superconductor jumps to the normal or resistive state with no change in the structure of moving vortex array. Another scenario predicts appearance of the vortex rivers at the instability point and jump of the superconductor to the normal or the resistive state but with strongly modified structure of the moving vorticies.

中文翻译：

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II 型超导带中的通量流动不稳定性：空间均匀与非均匀过渡

我们讨论了 II 型超导带中通量流动不稳定性 (FFI) 的两种可能机制。虽然导致这种不稳定性的非平衡效应的性质已被广泛接受（焦耳热和超导有序参数的有限弛豫时间），但仍然存在 FFI 如何在空间中发展的问题。根据一种情况，整个样品同时发生不稳定，超导体跳到正常或电阻状态，而移动涡流阵列的结构没有变化。另一种情景预测在不稳定点出现涡流河，超导体跳到正常状态或电阻状态，但运动涡流的结构发生了强烈的变化。