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Weak antilocalization (WAL) effect is commonly observed in 2D systems, or 3D topological insulators, topological semimetal systems. Here we report the clear sign of WAL effect in high quality Ta$_{0.7}$Nb$_{0.3}$Sb$_2$ single crystals, in below 50$^\circ$ K region. The chemical vapor transport method was employed to grow the single crystal samples, the high crystallization quality and uniform element distribution are verified by X-ray diffractions and electron microscopy techniques. Employing the Hall effect and two-band model fitting, the high carrier mobility (> 1000 cm$^2$V$^{-1}$s$^{-1}$ in 2 to 300$^\circ$ K region) and off-compensation electron/hole ratio are obtained. Due to the different angular dependence of WAL effect and the fermiology of Ta$_{0.7}$Nb$_{0.3}$Sb$_2$ single crystal, interesting magnetic-field-induced symmetry change is observed in angular magnetoresistance. These interesting transport properties will lead to more theoretical and applicational exploration in Ta$_{0.7}$Nb$_{0.3}$Sb$_2$ and related semimetal materials., Comment: 18 pages, 6 figures

Tabular data is arguably one of the most commonly used data structures in various practical domains, including finance, healthcare and e-commerce. The inherent heterogeneity allows tabular data to store rich information. However, based on a recently published tabular benchmark, we can see deep neural networks still fall behind tree-based models on tabular datasets. In this paper, we propose Trompt--which stands for Tabular Prompt--a novel architecture inspired by prompt learning of language models. The essence of prompt learning is to adjust a large pre-trained model through a set of prompts outside the model without directly modifying the model. Based on this idea, Trompt separates the learning strategy of tabular data into two parts. The first part, analogous to pre-trained models, focus on learning the intrinsic information of a table. The second part, analogous to prompts, focus on learning the variations among samples. Trompt is evaluated with the benchmark mentioned above. The experimental results demonstrate that Trompt outperforms state-of-the-art deep neural networks and is comparable to tree-based models., Comment: ICML'23 (poster)

Although the band topology of ZrGeSe has been studied via magnetic torque technique, the electronic transport behaviors related to the relativistic Fermions in ZrGeSe are still unknown. Here, we first report systematic electronic transport properties of high-quality ZrGeSe single crystals under magnetic fields up to 14 T. Resistivity plateaus of temperature dependent resistivity curves both in the presence and absence of magnetic fields as well as large, non-saturating magnetoresistance in low-temperature region were observed. By analyzing the temperature- and angular-dependent Shubnikov-de Haas oscillations and fitting it via the Lifshitz-Kosevich (LK) formula with the Berry phase being taken into account, we proved that Dirac fermions dominate the electronic transport behaviors of ZrGeSe and the presence of non-trivial Berry phase. First principles calculations demonstrate that ZrGeSe possesses Dirac bands and normal bands near Fermi surface, resulting in the observed magnetotransport phenomena. These results demonstrate that ZrGeSe is a topological nodal-line semimetal, which provides a fundamentally important platform to study the quantum physics of topological semimetals., Comment: 21 pages, 6 figures

A gap soliton is a solitonic state existing inside the band gap of an infinite-periodic exciton-polariton condensate (EPC). The combination of surface states and gap solitons forms the so named surface gap solitons (SGSs). We analyze the existence of SGSs near the interface between uniform and semi-infinite periodic EPCs. We find that SGSs exist only when the system is excited by a pump with low power and small width. As the pump power or width increases, SGSs become unstable., Comment: 4 pages, 4 figures

A ring dark soliton is a dark soltion occurring in higher dimensions. It is still unknown in microcavity-polariton condensates due to its instability. We find that a stable RDS cannot exist in a MPC without a defect. We then propose a way to create a stable RDS in a MPC by adding a defect with a ring structure to the system. A RDS pinned by the defect potential becomes stable. For various pump powers, we also investigate the stable regime of the RDS by tuning the strength and width of the defect potential. We conclude that the stable RDSs can be obtained., Comment: 4 pages, 4 figures

We theoretically explore the phase transition in inhomogeneous exciton-polariton condensates with variable pumping conditions. Through Bogoliubov excitations to the radial-symmetric solutions of complex Gross-Pitaevskii equation, we determine not only the bifurcation of stable and unstable modes by the sign of fluid compressibility but also two distinct stable modes which are characterized by the elementary excitations and the stability of singly quantized vortex. One state is the quasi-condensate BKT phase with Goldstone flat dispersion; the other state is the localized-BEC phase which exhibits linear-type dispersion and has an excitation energy gap at zero momentum., Comment: 17 pages, 4 figures

We study the dynamics of spontaneously formed vortices in homogeneous microcavity-polariton condensates (MPCs). We find that vortices are stable and appear spontaneously without stirring or rotating MPCs. The dip of the vortex core contains some background of reservoir polaritons and the visibility of a vortex is increasing with respect to the pump strength. The vortex radius is inversely proportional to the square root of the condensate density. Excitation energies of vortices at high and low pump powers are finite and zero, respectively. Vortices at low pump powers exhibit the short lifetime., Comment: 14 pages, 3 figures

We study non-equilibrium microcavity-polariton condensates (MPCs) in a harmonic potential trap theoretically. We calculate and analyze the steady state, collective-excitation modes and instability of MPCs. Within excitation modes, there exist Nambu-Goldstone modes that can reveal the pattern of the spontaneous symmetry breaking of MPCs. Bifurcation of the stable and unstable modes is identified in terms of the pumping power and spot size. The unstable mechanism associated with the inward supercurrent flow is characterized by the existence of a supersonic region within the condensate., Comment: 16 pages, 3 figures