We have studied theoretically the Kondo effect in the quantum dot(QD) within the whole range of temperature by using the equation-of-motion(EOM) technique based on the non-equilibrium Green function formalism. We have taken the finiteness of Coulomb correlation and the non-equilibrium effect into account by calculating the correlation terms emerged from the decoupling approximation using EOM method for the lesser Green function. We showed that the result is in good qualitative agreement with the results of NCA, NRG and NRPT, etc., even using EOM method which is being recognized as a 'conventional' method.
The results are the generalization into the pseudo-equilibrium state of the Refs. 32,33 and can be used to describe a non-equilibrium state under the bias voltage which is not so large.
We present the theory of quasiparticle transport in perturbatively small inhomogeneous magnetic fields across the ballistic-to-hydrodynamic crossover. In the hydrodynamic limit, the resistivity $ρ$ generically grows proportionally to the rate of momentum-conserving electron-electron collisions at large enough temperatures $T$. In particular, the resulting flow of electrons provides a simple scenario where viscous effects suppress conductance below the ballistic value. This new mechanism for $ρ\propto T^2$ resistivity in a Fermi liquid may describe low $T$ transport in single-band $\mathrm{SrTi…
Flat electronic bands are counterintuitive: with the electron velocity vanishing, our conventional notions of quasiparticle transport are no longer valid. We here study the quantum transport in the generalized families of perfectly flat bands [PRB 105, L241102 (2022)], and find that while the conventional contributions indeed vanish, the quantum-geometric contribution gives rise to the enhanced electronic transport. This contribution is connected to the Wannier orbital quantization in the perfectly flat bands, and is present only for geometrically-nontrivial bands (for example, flat Chern band…
In low-dimensional systems, the combination of reduced dimensionality, strong interactions, and topology has led to a growing number of many-body quantum phenomena. Thermal transport, which is sensitive to all energy-carrying degrees of freedom, provides a discriminating probe of emergent excitations in quantum materials and devices. However, thermal transport measurements in low dimensions are dominated by the phonon contribution of the lattice, requiring an experimental approach to isolate the electronic thermal conductance. Here, we show how the measurement of nonlocal voltage fluctuations …
Effects of Fe substitution on the electronic, transport, and magnetic properties of ZnGa$_2$O$_4$: A systematic ab-initio study
采用密度泛函方法研究了Fe掺杂到宽禁带尖晶石ZnGa $_2$ O $_4$的四面体和八面体阳离子位的结构.我们计算了不同的取代的电子结构，并讨论了考虑不同近似的交换相关势的每种情况下的磁性和输运性质。我们表明，对于某些掺杂的情况下，获得的预测行为的显着差异取决于所采用的交换相关电位。概述了掺杂系统作为磁性半导体的可能应用。
Metallic ground state and glassy transport in single crystalline URh$_2$Ge$_2$: Enhancement of disorder effects in a strongly correlated electron system
本文详细研究了中等无序重费米子系统URh $_2$ Ge $_2$的电子输运性质。对于这种材料，我们发现在一个单一的晶体化合物的玻璃态电子输运。我们推导出的电导率的温度依赖性，并建立通过光学电导率和霍尔效应测量的金属性。电子输运性质的整体行为非常类似于金属玻璃，在低温下额外的轻微自旋无序的贡献。我们认为，这种玻璃态的电子行为在晶体化合物中反映了增强的无序效应的结果，强的电子相关。
Using the Lindblad equation approach, we study the nonequilibrium stationary state of a benzene ring connected to two reservoirs in the large bias regime, a prototype of a generic molecular electronic device. We show the emergence of an optimal working point (corresponding to a change in the monotonicity of the stationary current, as a function of the applied bias) and its robustness against chemical potential and bond disorder.
The ``flow'' of electric currents and heat in standard metals is diffusive with electronic motion randomized by impurities. However, for ultraclean metals, electrons can flow like water with their flow being described by the equations of hydrodynamics. While theoretically postulated, this situation was highly elusive for decades. In the last decade, several experimental groups have found strong indications for this type of flow, especially in graphene-based devices. In this review, we give an overview of some of the recent key developments, both on the theoretical and experimental side.
