Vortex dynamics and possible vortex states just below the vortex-glass phase
Vortex dynamics and possible vortex states just below the vortex-glass phase
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DOI：
10.1103/physrevb.70.014509
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发表时间：
2004-07
影响因子：
3.7
通讯作者：
S. Okuma;M. Kamada
中科院分区：
文献类型：
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作者：
S. Okuma;M. Kamada
我们测量了非晶态${\mathrm{Mo}}_{x}{\mathrm{Si}}_{1\ensuremath{-}x}$厚膜在涡旋-玻璃(VG)相变附近从零场到高场的电流感生电压噪声{S}_{V}$。与温度T无关，在迈斯纳相中，${S}_{V}$(hl{H}_{c1})$最高。应用超过${H}_{c1}$的$H$时，${S}_{V}$突然下降并降至背景水平。随着$H的进一步增加，${S}_{V}$在特征场${H}_{lg}^{0}(⪡{H}_{g})$处开始上升，并在接近${H}_{g}$之前出现由Vg的塑性流动引起的宽峰。结合科尔比诺圆盘的数据，我们认为清洁的单晶中的边缘污染效应在无序薄膜中并不重要。在所研究的$T$范围内，${H}{lg}^{0}(T)$表现出冷却的增加，这不同于$T$独立的无序驱动的相变。我们将场域{H}{c1}(T)Lh(T)L{H}{lg}^{0}(T)$解释为不同于VG相的涡旋态。
We have measured current-induced voltage noise ${S}_{V}$ of thick amorphous ${\mathrm{Mo}}_{x}{\mathrm{Si}}_{1\ensuremath{-}x}$ films in various fields $H$ from zero to high fields near the vortex-glass (VG) transition ${H}_{g}$. Irrespective of temperature $T$, ${S}_{V}$ is highest in the Meissner phase $(Hl{H}_{c1})$. With applying $H$ that exceeds ${H}_{c1}$, ${S}_{V}$ decreases abruptly and falls to the background level. With further increasing $H$, ${S}_{V}$ then starts to rise at characteristic field ${H}_{Lg}^{0}(⪡{H}_{g})$ and the broad peak resulting from a plastic-flow motion of VG occurs before ${H}_{g}$ is approached. Combined with the ${S}_{V}$ data for the Corbino disk, we suggest that the edge-contamination effects reported in the clean ${\mathrm{NbSe}}_{2}$ single crystals are not important in our disordered films. Within the $T$ range studied, ${H}_{Lg}^{0}(T)$ shows an increase on cooling, which is different from the $T$-independent disorder-driven transition. We interpret the field regime ${H}_{c1}(T)lH(T)l{H}_{Lg}^{0}(T)$ as the vortex state different from the VG phase.