arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1507.00546hep-thgr-qc
收藏

块状$2$型场与全息铁磁相变

Massive $2$-form field and holographic ferromagnetic phase transition

Rong-Gen Cai, Run-Qiu Yang, Ya-Bo Wu, Cheng-Yuan Zhang

摘要:

在本文中,我们研究了一些详细的全息铁磁相变在一个AdS ${_4}$黑膜背景中通过引入一个大质量的2型场耦合到体的麦克斯韦场强度。在两种探测极限中,一种是忽略2型场对背景几何和Maxwell场的反作用,另一种是同时忽略Maxwell场和2型场的反作用,我们发现,当温度足够低时,自发磁化和铁磁相变总是发生,且临界行为相似。在第二探针极限下,用半解析方法计算了直流电阻率,发现在某些材料中直流电阻率表现为庞磁阻效应。在第一探测极限的情况下,我们得到了全息模型在临界温度附近的离壳自由能,并与Ising类模型进行了比较。我们还研究了反反应效应,发现相变总是二级的。此外,我们还在具有负宇宙学常数的Einstein-Maxwell-2-form场论中找到了一个解析的类Reissner-Norström黑膜解.

英文摘要:

In this paper, we investigate in some detail the holographic ferromagnetic phase transition in an AdS${_4}$ black brane background by introducing a massive 2-form field coupled to the Maxwell field strength in the bulk. In the two probe limits, one is to neglect the back reaction of the 2-form field to the background geometry and to the Maxwell field, and the other to neglect the back reaction of both the Maxwell field and the 2-form field, we find that the spontaneous magnetization and the ferromagnetic phase transition always happen when the temperature gets low enough with similar critical behavior. We calculate the DC resistivity in a semi-analytical method in the second probe limit and find it behaves as the colossal magnetic resistance effect in some materials. In the case with the first probe limit, we obtain the off-shell free energy of the holographic model near the critical temperature and compare with the Ising-like model. We also study the back reaction effect and find that the phase transition is always second order. In addition, we find an analytical Reissner-Norström-like black brane solution in the Einstein-Maxwell-2-form field theory with a negative cosmological constant.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑