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This study introduces an advanced machine learning method for predicting soccer players' market values, combining ensemble models and the Shapley Additive Explanations (SHAP) for interpretability. Utilizing data from about 12,000 players from Sofifa, the Boruta algorithm streamlined feature selection. The Gradient Boosting Decision Tree (GBDT) model excelled in predictive accuracy, with an R-squared of 0.901 and a Root Mean Squared Error (RMSE) of 3,221,632.175. Player attributes in skills, fitness, and cognitive areas significantly influenced market value. These insights aid sports industry stakeholders in player valuation. However, the study has limitations, like underestimating superstar players' values and needing larger datasets. Future research directions include enhancing the model's applicability and exploring value prediction in various contexts., Comment: 13pages, 6figures

Synthetic gauge fields have provided physicists with a unique tool to explore a wide range of fundamentally important phenomena. However, most experiments have been focusing on synthetic vector gauge fields. The very rich physics brought by coupling tensor gauge fields to fracton phase of matter remain unexplored in laboratories. Here, we propose schemes to realize synthetic tensor gauge fields that address dipoles instead of single-particles. A lattice tilted by a strong linear potential and a weak quadratic potential yields a rank-2 electric field for a lineon formed by a particle-hole pair. Such a rank-2 electric field leads to a new type of Bloch oscillations, which modulate the quadrupole moment and preserve the dipole moment of the system. In higher dimensions, the interplay between interactions and vector gauge potentials imprints a phase to the ring-exchange interaction and thus generates synthetic tensor gauge fields for planons. Such tensor gauge fields make it possible to realize a dipolar Harper-Hofstadter model in laboratories. The resultant dipolar Chern insulators feature chiral edge currents of dipoles in the absence of net charge currents., Comment: 6+5 pages, 4+5 figures

The electric dipole moment (EDM) plays a crucial role in determining the interaction strength of an atom with electric fields, making it paramount to quantum technologies based on coherent atomic control. We propose a scheme for engineering the potential in a Paul trap to realize a two-level quantum system with a giant EDM formed by the motional states of a trapped electron. We show that, under realistic experimental conditions, the EDM can significantly exceed the ones attainable with Rydberg atoms. Furthermore, we show that such artificial atomic dipoles can be efficiently initialized, readout, and coherently controlled, thereby providing a potential platform for quantum technologies such as ultrahigh-sensitivity electric-field sensing., Comment: 7 pages, 4 5 figures + 26 pages Supplemental Material. Comments are welcome

In a recently demonstrated quantum-state tomography scheme [Phys. Rev. Lett. 124, 010405 (2020)], a random control field is locally applied to a multipartite system to reconstruct the full quantum state of the system through single-observable measurements. Here, we analyze the robustness of such a tomography scheme against measurement errors. We characterize the sensitivity to measurement errors using the logarithm of the condition number of a linear system that fully describes the tomography process. Using results from random matrix theory we derive the scaling law of the logarithm of this condition number with respect to the system size when Haar-random evolutions are considered. While this expression is independent on how Haar randomness is created, we also perform numerical simulations to investigate the temporal behavior of the robustness for two specific quantum systems that are driven by a single random control field. Interestingly, we find that before the mean value of the logarithm of the condition number as a function of the driving time asymptotically approaches the value predicted for a Haar-random evolution, it reaches a plateau whose length increases with the system size., Comment: 10 pages, 4 figures

Recently, Graph Neural Networks (GNNs) achieve remarkable success in Recommendation. To reduce the influence of data sparsity, Graph Contrastive Learning (GCL) is adopted in GNN-based CF methods for enhancing performance. Most GCL methods consist of data augmentation and contrastive loss (e.g., InfoNCE). GCL methods construct the contrastive pairs by hand-crafted graph augmentations and maximize the agreement between different views of the same node compared to that of other nodes, which is known as the InfoMax principle. However, improper data augmentation will hinder the performance of GCL. InfoMin principle, that the good set of views shares minimal information and gives guidelines to design better data augmentation. In this paper, we first propose a new data augmentation (i.e., edge-operating including edge-adding and edge-dropping). Then, guided by InfoMin principle, we propose a novel theoretical guiding contrastive learning framework, named Learnable Data Augmentation for Graph Contrastive Learning (LDA-GCL). Our methods include data augmentation learning and graph contrastive learning, which follow the InfoMin and InfoMax principles, respectively. In implementation, our methods optimize the adversarial loss function to learn data augmentation and effective representations of users and items. Extensive experiments on four public benchmark datasets demonstrate the effectiveness of LDA-GCL., Comment: Accepted and to appear at DASFAA2023

The click behavior is the most widely-used user positive feedback in recommendation. However, simply considering each click equally in training may suffer from clickbaits and title-content mismatching, and thus fail to precisely capture users' real satisfaction on items. Dwell time could be viewed as a high-quality quantitative indicator of user preferences on each click, while existing recommendation models do not fully explore the modeling of dwell time. In this work, we focus on reweighting clicks with dwell time in recommendation. Precisely, we first define a new behavior named valid read, which helps to select high-quality click instances for different users and items via dwell time. Next, we propose a normalized dwell time function to reweight click signals in training for recommendation. The Click reweighting model achieves significant improvements on both offline and online evaluations in real-world systems., Comment: 5 pages, accepted by WWW-2023 Companion

The Benalcazar-Bernevig-Hughes(BBH) model is one of the most representative higher-order topological insulators with different bulk-edge correspondence comparing conventional topological states. In this work, we propose to realize a couple-BBH model with glide reflection symmetry by coupling two topologically distinct BBH models. Such a system gives rise to intriguing properties beyond the traditional BBH model. A topological phase transition from higher-order topological phase to a semimetal has been predicted in this system. Furthermore, the band crossing points and nodal ring protected by glide reflection symmetry has also been explored. Our work provides a viewpoint to demonstrate the versatile phenomena induced by the interplay between higher-order topology and nonsymmorphic symmetries., Comment: 9 pages, 8 figures, comments are welcome

The features of topological physics can manifest in a variety of physical systems in distinct ways. Periodically driven systems, with the advantage of high flexibility and controllability, provide a versatile platform to simulate many topological phenomena and may lead to novel phenomena that can not be observed in the absence of driving. Here we investigate the influence of realistic experimental noise on the realization of a two-level system under a two-frequency drive that induces topologically nontrivial band structure in the two-dimensional Floquet space. We propose a dynamical decoupling scheme that sustains the topological phase transition overcoming the influence of dephasing. Therefore, the proposal would facilitate the observation of topological frequency conversion in the solid state spin system, e.g. NV center in diamond., Comment: 9 pages, 6 figures

The higher-order topological insulator (HOTI) is a new type of topological system which has special bulkedge correspondence compared with conventional topological insulators. In this work, we propose a scheme to realize Floquet HOTI in ultracold atom systems. With the combination of periodically spin-dependent driving of the superlattices and a next-next-nearest-neighbor d-wave-like anisotropic coupling term between different spin components, a Floquet second-order topological insulator with four zero-energy corner states emerges, whose Wannier bands are gapless and exhibit interesting bulk topology. Furthermore, the anisotropic coupling with nearest-neighbor form will also induce some intriguing topological phenomena, e.g. non-topologically protected corner states and topological semimetal for two different types of lattice structures respectively. Our scheme may give insight into the construction of different types of higher-order topological insulators in synthetic systems. It also provides an experimentally feasible platform to research the relations between different types of topological states and may have a wide range of applications in future.

Optomechanical systems offer unique opportunities to explore macroscopic quantum state and related fundamental problems in quantum mechanics. Here, we propose a quantum optomechanical system involving exchange interaction between spin angular momentum of light and a torsional oscillator. We demonstrate that this system allows coherent control of the torsional quantum state of a torsional oscillator on the single photon level, which facilitates efficient cooling and squeezing of the torsional oscillator. Furthermore, the torsional oscillator with a macroscopic length scale can be prepared in Schr\"odinger cat-like state. Our work provides a platform to verify the validity of quantum mechanics in macroscopic systems on the micrometer and even centimeter scale., Comment: 5 pages + 14 pages of appendices, 9 figures

Superradiant phase transition represents an important quantum phenomenon that shows the collective excitations based on the coupling between atoms and cavity modes. The spin-orbit coupling is another quantum effect which induced from the interaction of the atom internal degrees of freedom and momentum of center-of-mass. In this work, we consider the cavity assisted dynamical spin-orbit coupling which comes from the combination of these two effects. It can induce a series of interesting quantum phenomena, such as the flat spectrum and the singularity of the excitation energy spectrum around the critical point of quantum phase transition. We further discuss the influence of atom decay and nonlinear coupling to the phase diagram. The atom decay suppresses the singularity of the phase diagram and the nonlinear coupling can break the symmetric properties of the phase transition. Our work provide the theoretical methods to research the rich quantum phenomena in this dynamic many-body systems., Comment: 8 pages, 6 figures

Quantum criticality, as a fascinating quantum phenomenon, may provide significant advantages for quantum sensing. Here we propose a dynamic framework for quantum sensing with a family of Hamiltonians that undergo quantum phase transitions (QPT). By giving the formalism of the quantum Fisher information (QFI) for quantum sensing based on critical quantum dynamics, we demonstrate its divergent feature when approaching the critical point. We illustrate the basic principle and the details of experimental implementation using quantum Rabi model. The framework is applicable to a variety of examples and does not rely on the stringent requirement for particular state preparation or adiabatic evolution. It is expected to provide a route towards the implementation of criticality-enhanced quantum sensing.

The quantum Cram\'er-Rao bound sets a fundamental limit on the accuracy of unbiased parameter estimation in quantum systems, relating the uncertainty in determining a parameter to the inverse of the quantum Fisher information. We experimentally demonstrate near saturation of the quantum Cram\'er-Rao bound in the phase estimation of a solid-state spin system, provided by a nitrogen-vacancy center in diamond. This is achieved by comparing the experimental uncertainty in phase estimation with an independent measurement of the related quantum Fisher information. The latter is independently extracted from coherent dynamical responses of the system under weak parametric modulations, without performing any quantum-state tomography. While optimal parameter estimation has already been observed for quantum devices involving a limited number of degrees of freedom, our method offers a versatile and powerful experimental tool to explore the Cram\'er-Rao bound and the quantum Fisher information in systems of higher complexity, as relevant for quantum technologies.

Topological charge pumping represents an important quantum phenomenon that shows the fundamental connection to the topological properties of dynamical systems. Here, we introduce a pumping process in a spin-dependent double-well optical lattice with glide symmetry. In the dynamic process, the glide symmetry protects the band touching points and topological properties of the system are characterised by the non-Abelian Berry curvature. By engineering suitable form of interaction between different spin components, the model not only demonstrates topological phase transition, but also shows hybridisation between the spatial and temporal domain with novel topological features captured by the Wilson line along the synthetic directions. Our work provides a new model based on ultracold atoms towards the implementation of versatile topological matters and topological phenomena., Comment: 5 pages, 3 figures

Geometry and topology are fundamental concepts, which underlie a wide range of fascinating physical phenomena such as topological states of matter and topological defects. In quantum mechanics, the geometry of quantum states is fully captured by the quantum geometric tensor. Using a qubit formed by an NV center in diamond, we perform the first experimental measurement of the complete quantum geometric tensor. Our approach builds on a strong connection between coherent Rabi oscillations upon parametric modulations and the quantum geometry of the underlying states. We then apply our method to a system of two interacting qubits, by exploiting the coupling between the NV center spin and a neighboring $^{13}$C nuclear spin. Our results establish coherent dynamical responses as a versatile probe for quantum geometry, and they pave the way for the detection of novel topological phenomena in solid state.