• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Experimental and Theoretical Physics >Anomalous resistivity and the origin of heavy mass in the two-band hubbard model with one narrow band1
【24h】

Anomalous resistivity and the origin of heavy mass in the two-band hubbard model with one narrow band1

机译：具有一个窄带的两波段Hubbard模型的反常电阻率和重物的起源1

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

We search for marginal Fermi-liquid behavior [1] in the two-band Hubbard model with one nar- row band. We consider the limit of low electron densities in the bands and strong intraband and interband Hubbard interactions. We analyze the influence of electron polaron effect [2] and other mechanisms of mass enhancement (related to momentum dependence of the self-energies) on the effective mass and scattering times of light and heavy components in the clean case (electron-electron scattering and no impurities). We find the tendency towards phase separation (towards negative partial compressibility of heavy particles) in the 3D case for a large mismatch between the densities of heavy and light bands in the strong-coupling limit. We also observe that for low temperatures and equal densities, the homogeneous state resistivity R(T) ～ T~2 behaves in a Fermi-liquid fashion in both 3D and 2D cases. For temperatures higher than the effective band- width for heavy electrons T >, the coherent behavior of the heavy component is totally destroyed. The heavy particles move diffusively in the surrounding of light particles. At the same time, the light particles scat- ter on the heavy ones as if on immobile (static) impurities. In this regime, the heavy component is marginal, while the light one is not. The resistivity saturates for T > in the 3D case. In 2D, the resistivity has a max- imum and a localization tail due to weak-localization corrections of the Altshuler-Aronov type [3]. Such behavior of resistivity could be relevant for some uranium-based heavy-fermion compounds like UNi _2Al_3 in 3D and for some other mixed-valence compounds possibly including layered manganites in 2D. We also briefly consider the superconductive (SC) instability in the model. The leading instability is towards the p-wave pairing and is governed by the enhanced Kohn-Luttinger [4] mechanism of SC at low electron den- sity. The critical temperature corresponds to the pairing of heavy electrons via polarization of the light ones in 2D.
机译：我们在一个带一排窄带的两带式Hubbard模型中搜索边际费米液体行为[1]。我们考虑了带内低电子密度以及强带内和带间Hubbard相互作用的极限。我们分析了电子极化子效应[2]和其他质量增强机制（与自能的动量依赖性有关）对清洁情况下轻重组分的有效质量和散射时间（电子-电子散射和无杂质）。我们发现在3D情况下，在强耦合极限中，重带和轻带的密度之间存在较大的不匹配，相分离的趋势（朝着重颗粒的负局部可压缩性）。我们还观察到，在低温和等密度情况下，在3D和2D情况下，均质态电阻率R（T）〜T〜2均表现为费米液体的形式。对于高于重电子的有效带宽T>的温度，重组分的相干行为将被完全破坏。重粒子在轻粒子周围扩散扩散。同时，轻粒子会散布在重粒子上，就像固定的（静态）杂质一样。在这种情况下，重的部分是边缘，轻的部分则不是。在3D情况下，电阻率在T>时达到饱和。在二维中，由于Altshuler-Aronov型的弱定位校正，电阻率具有最大值和定位尾部[3]。电阻率的这种行为可能与某些铀基重金属化合物（如3D中的UNi _2Al_3）以及某些其他混合价化合物（可能包括2D层状锰矿）有关。我们还简要考虑了模型中的超导（SC）不稳定性。主导的不稳定性是朝向p波对，并由低电子密度下增强的SC的Kohn-Luttinger [4]机制控制。临界温度对应于二维中轻质电子的极化对重电子的配对。

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