...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nuclear physics, B >Quantum phases, supersolids and quantum phase transitions of interacting bosons in frustrated lattices
【24h】

Quantum phases, supersolids and quantum phase transitions of interacting bosons in frustrated lattices

机译：挫折晶格中相互作用的玻色子的量子相，超固体和量子相变

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

By using the dual vortex method (DVM), we develop systematically a simple and effective scheme to use the vortex degree of freedoms on dual lattices to characterize the symmetry breaking patterns of the boson insulating states in the direct lattices. Then we apply our scheme to study quantum phases and phase transitions in an extended boson Hubbard model slightly away from 1/3 (2/3) filling on frustrated lattices such as triangular and Kagome lattice. In a triangular lattice at 1/3, we find a X-CDW, a stripe CDW phase which was found previously by a density operator formalism (DOF). Most importantly, we also find a new CDW-VB phase which has both local CDW and local VB orders, in sharp contrast to a bubble CDW phase found previously by the DOF. In the Kagome lattice at 1/3, we find a VBS phase and a 6-fold CDW phase. Most importantly, we also identify a CDW-VB phase which has both local CDW and local VB orders which was found in previous QMC simulations. We also study several other phases which are not found by the DVM. By analyzing carefully the saddle point structures of the dual gauge fields in the translational symmetry breaking sides and pushing the effective actions slightly away from the commensurate filling f=1/3 (2/3), we classified all the possible types of supersolids and analyze their stability conditions. In a triangular lattice, there are X-CDW supersolid, stripe CDW supersolid, but absence of any valence bond supersolid (VB-SS). There are also a new kind of supersolid: CDW-VB supersolid. In a Kagome lattice, there are 6-fold CDW supersolid, stripe CDW supersolid, but absence of any valence bond supersolid (VB-SS). There are also a new kind of supersolid: CDW-VB supersolid. We show that independent of the types of the SS, the quantum phase transitions from solids to supersolids driven by a chemical potential are in the same universality class as that from a Mott insulator to a superfluid, therefore have exact exponents z=2, ν=1/2, η = 0 (with logarithmic corrections). Excitation spectra of all these insulating phases and supersolid phases are also studied. Implications on QMC simulations with both nearest neighbor and next nearest neighbor interactions in both lattices are given. Some possible intrinsic problems of the DOF in identifying the insulating phases are also pointed out.
机译：通过使用双涡旋方法（DVM），我们系统地开发了一种简单有效的方案，利用双晶格上的涡旋自由度来表征直接晶格中玻色子绝缘态的对称破坏模式。然后，我们将我们的方案应用于在扩展玻色子Hubbard模型中研究量子相和相变的过程，该模型稍微远离填充在受挫晶格（例如三角形和Kagome晶格）上的1/3（2/3）。在1/3的三角晶格中，我们找到了X-CDW，这是条纹CDW相，以前是由密度算符形式（DOF）发现的。最重要的是，我们还发现了一个新的CDW-VB阶段，该阶段同时具有本地CDW和本地VB订单，这与自由度以前发现的气泡CDW阶段形成了鲜明的对比。在1/3的Kagome晶格中，我们发现VBS相和6倍CDW相。最重要的是，我们还确定了CDW-VB阶段，该阶段同时具有本地CDW和本地VB订单，这在先前的QMC模拟中可以找到。我们还研究了DVM找不到的其他几个阶段。通过仔细分析平移对称破断侧的双轨距场的鞍点结构，并将有效作用略微推离相应的填充f = 1/3（2/3），我们对所有可能的超固体类型进行了分类并进行了分析其稳定性条件。在三角晶格中，存在X-CDW超固体，条纹CDW超固体，但不存在任何价键超固体（VB-SS）。还有一种新的超固体：CDW-VB超固体。在Kagome晶格中，存在6倍CDW超固体，条纹CDW超固体，但不存在任何价键超固体（VB-SS）。还有一种新的超固体：CDW-VB超固体。我们表明，与SS的类型无关，由化学势驱动的从固体到超固体的量子相变与从Mott绝缘体到超流体的量子相变具有相同的通用性，因此具有精确的指数z = 2，ν= 1/2，η= 0（对数校正）。还研究了所有这些绝缘相和超固相的激发光谱。给出了在两个晶格中具有最近邻和次近邻相互作用的QMC模拟的含义。指出了DOF在识别绝缘相中可能存在的内在问题。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号