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A theoretical investigation has been carried out to study the effect of strong electrostatic interaction on the dust acoustic shock structures in strongly coupled dusty plasma with dust charge fluctuations.The fluid approach is employed,in which the strong electrostatic interaction is modeled by effective electrostatic temperature.A Burger-like equation,the coefficients of which are significantly modified by effects of strong coupling and dust charge Ructuation,is derived.It is shown that the combined effects of dust charge Ructuation,the ion/electron temperature,the ion/electron population,and strong coupling effect modify the basic properties of the dust acoustic waves in such a strongly coupled dusty plasma.The results of this work are compared with those observed by some laboratory experiments. 相似文献
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当考虑电子间的库伦排斥相互作用,以及电荷、自旋和轨道之间的相互耦合时,诸多超越
了近自由电子框架的新奇量子态涌现而出,如非常规超导态和量子自旋液体等。对这些新奇物态
的认知不仅会拓展现有的知识框架,也有望引发新一轮的量子科技革命。因此,对强关联物理的
研究是当下凝聚态物理领域的前沿课题。铜基高温超导体的母体是一种莫特绝缘体,在传统的能
带论之下被预言为金属态。然而电子间的强关联行为使得它表现出绝缘体的性质。由于莫特绝缘
体中库伦相互作用致使能隙打开并冻结其中的电荷自由度,所以在该体系中难以开展电输运性质
的测量研究。作为一种对于元激发(不仅包括电子,还包括磁振子、自旋子等)敏感的探针,热输
运测量在强关联电子系统的研究中发挥着重要的作用。本文回顾了近些年在非常规超导、重费米
子系统和量子自旋液体研究中一些有趣的纵向热输运性质的研究成果,并与我们近期发表的运用
横向热导率测量热霍尔现象的综述文章相互补充。 相似文献
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对于欠掺杂铜氧化物超导体 ,当温度T高于超导转变温度Tc 但低于赝能隙温度T 时 ,便有正常态赝能隙打开 (在ab平面布里渊区的角隅位置 ) .赝能隙的存在对c轴方向的电荷输运起阻碍作用 ,结果导致正常态输运行为的强二维性 ,即电阻率ρab(T)的金属行为和 ρc(T)的绝缘体行为 .当温度降至Tc 以下 ,层间的约瑟夫森耦合使得材料转变为三维各向同性超导态 .其中有效维数的转变一直是凝聚态物理的一个热点课题 .上述维数转变的问题也存在于非超导的层状强关联金属中 ,例如 (Bi0 5Pb0 5) 2 Ba3 Co2 Oy(简称BPB CO ,它… 相似文献
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Electrical properties of C/Ni films are studied using four mosaic targets made of pure graphite and stripes of nickel with the surface areas of 1.78,3.21,3.92 and 4.64%.The conductivity data in the temperature range of400–500 K shows the extended state conduction.The conductivity data in the temperature range of 150–300 K shows the multi-phonon hopping conduction.The Berthelot-type conduction dominates in the temperature range of 50–150 K.The conductivity of the films in the temperature range about 50 K is described in terms of variable-range hopping conduction.In low temperatures,the localized density of state around Fermi level(F)for the film deposition with 3.92% nickel has a maximum value of about 56.2×10~(17)cm~(-3)eV~(-1) with the minimum average hopping distance of about 3.43 × 10~(-6) cm. 相似文献
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J. E. Avron S. Bachmann G. M. Graf I. Klich 《Communications in Mathematical Physics》2008,280(3):807-829
Using operator algebraic methods we show that the moment generating function of charge transport in a system with infinitely
many non-interacting Fermions is given by a determinant of a certain operator in the one-particle Hilbert space. The formula
is equivalent to a formula of Levitov and Lesovik in the finite dimensional case and may be viewed as its regularized form
in general. Our result embodies two tenets often realized in mesoscopic physics, namely, that the transport properties are
essentially independent of the length of the leads and of the depth of the Fermi sea. 相似文献
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In the tight-binding random Hamiltonian on Z
d
, we consider the charge transport induced by an electric potential which varies sufficiently slowly in time, and prove that it is almost surely equal to zero at high disorder. In order to compute the charge transport, we adopt the adiabatic approximation and prove a weak form of adiabatic theorem while there is no spectral gap at the Fermi energy. 相似文献
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Transport of localized nonlinear excitations in disordered media is an interesting and important topic in modern physics. Investigated in this work is transport of two‐dimensional (2D) solitons for a nonlinear Schrödinger equation with inhomogeneous nonlocality and disorder. We use the variational method to show that, the shape (size) of solitons can be manipulated through adjusting the nonlocality, which, in turn, affects the soliton mobility. Direct numerical simulations reveal that the influence of disorder on the soliton transport accords with our analysis by the variational method. Besides, we have demonstrated an anisotropic transport of the 2D nonautonomous solitons as well. Our study is expected to shed light on modulating solitons through material properties for specifying their transport in disordered media. 相似文献
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Metals are typically good conductors in which the abilities to transport charge and to transport heat can be related through the Wiedemann-Franz law. Here we report on an abnormal charge and heat transport in polycrystalline metallic nanostructures in which the ability to transport charge is weakened more obviously than that to transport heat. We attribute it to the influence of the internal grain boundaries and have formulated a novel relation to predict the thermal conductivity. The Wiedemann-Franz law is then modified to account for the influence of the grain boundaries on the charge and heat transport with the predictions now agreeing well with the measured results. 相似文献
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《理论物理通讯》2017,(7)
The theory of dynamical(wake) potential behind a moving test charge in a weakly coupled dusty plasma is extended to that including of strong interaction between dust grains. Such strong interaction is included in the dielectric response function by a generalized hydrodynamic(GH) fluid model. It is shown that the strong interaction between dusts including the lattice spacing correction has a significant effect on the wake potential in dusty plasma. This may be used to investigate basic features of phase transition and possibility of lattice formation of dusty plasma. 相似文献
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Burdastyh M. V. Postolova S. V. Derbezov I. A. Gaisler A. V. Diamantini M. C. Trugenberger C. A. Vinokur V. M. Mironov A. Yu. 《JETP Letters》2019,109(12):795-798
JETP Letters - We investigate the evolution of the electronic transport in disordered NbTiN films at the insulating side of the superconductor-insulator transition as function of the effective... 相似文献
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氧化石墨烯膜各向异性热传输特性研究 总被引:1,自引:0,他引:1
氧化石墨烯膜是一类新型的层状材料。本文报道了氧化石墨烯膜的面内和垂直于面方向的热扩散率和热导率,发现垂直于面方向的热导率比面内热导率低一个数量级,展示了明显的各向异性特征。氧化石墨烯膜的导热系数远低于单层石墨烯的导热系数,其原因主要是由于氧化石墨烯膜间的接触热租和氧化石墨烯膜本身导热系数较低造成的。 相似文献
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运用气相输运技术在不同的衬底上制备ZnO薄膜,同时对这些ZnO薄膜的表面形貌、晶体结构和光学特性进行表征。在扫描电子显微镜图像上可以看到,相比没有镀金的Si衬底,ZnO纳米颗粒在镀金的Si衬底上的生长尺寸较大。X射线衍射测试结果表明,在Si(111)和Si(100)衬底上生长的ZnO薄膜显示出不同的六角纤锌矿结构的衍射峰,但没有出现立方闪锌矿ZnO结构的衍射峰。在镀金的Si衬底上,ZnO薄膜生长取向主要为c轴方向。此外,所有ZnO样品的光致发光谱上均只出现一个狭窄且强的紫外峰,约在389 nm(3.19 eV)波长处。 相似文献
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在不同导电衬底(Au,Al和ITO)上制备了PTCDA薄膜,用XRD和AFM技术研究了PTCDA薄膜的结构和表面形貌。结果表明,薄膜中的大部分PTCDA分子平面与衬底不平行,这表明薄膜垂直方向的电流传导将以电子传输为主;在ITO和Au衬底上生长的PTCDA薄膜晶粒排列规则,在薄膜垂直方向呈现出较好的电子传输性能;而在Al衬底上生长的PTCDA薄膜晶粒排列无序,电子传输性能差。通过制备单层结构有机薄膜器件,研究了PTCDA薄膜垂直方向的电子迁移率。综合应用金属-有机界面的热电子发射理论和有机层体内空间电荷限制传导理论,并考虑电场强度对迁移率变化的影响,对ITO/PTCDA/Al器件的电流密度-电压曲线进行拟合,得到ITO衬底上生长的PTCDA薄膜在垂直方向随电场强度变化的电子迁移率数值。 相似文献
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Bykov T. A. Kasatov D. A. Kolesnikov Ia. A. Koshkarev A. M. Makarov A. N. Ostreinov G. M. Sokolova E. O. Taskaev S. Yu. Shchudlo I. M. 《Technical Physics》2021,66(1):98-102
Technical Physics - A neutron source composed of a tandem accelerator with vacuum insulation and a lithium target is used to develop the boron neutron capture therapy and other applications. The... 相似文献