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Controlling topological phases of light has allowed experimental observations of abundant topological phenomena and development of robust photonic devices. The prospect of more sophisticated controls with topological photonic devices for practical implementations requires high-level programmability. Here, we demonstrate a fully programmable topological photonic chip with large-scale integration of silicon photonic nanocircuits and microresonators. Photonic artificial atoms and their interactions in our compound system can be individually addressed and controlled, therefore allowing arbitrary altering of structural parameters and geometrical configurations for the observations of dynamic topological phase transitions and diverse photonic topological insulators. By individually programming artificial atoms on the generic chip, it has allowed comprehensive statistic characterisations of topological robustness against relatively weak disorders, as well as counterintuitive topological Anderson phase transitions induced by strong disorders. Our generic topological photonic chip that can be rapidly reprogrammed to implement multifunctionalities, prototypes a flexible and versatile platform for possible applications across fundamental science and topological technologies.

The performance of visual SLAM in complex, real-world scenarios is often compromised by unreliable feature extraction and matching when using handcrafted features. Although deep learning-based local features excel at capturing high-level information and perform well on matching benchmarks, they struggle with generalization in continuous motion scenes, adversely affecting loop detection accuracy. Our system employs a Model-Agnostic Meta-Learning (MAML) strategy to optimize the training of keypoint extraction networks, enhancing their adaptability to diverse environments. Additionally, we introduce a coarse-to-fine feature tracking mechanism for learned keypoints. It begins with a direct method to approximate the relative pose between consecutive frames, followed by a feature matching method for refined pose estimation. To mitigate cumulative positioning errors, DK-SLAM incorporates a novel online learning module that utilizes binary features for loop closure detection. This module dynamically identifies loop nodes within a sequence, ensuring accurate and efficient localization. Experimental evaluations on publicly available datasets demonstrate that DK-SLAM outperforms leading traditional and learning based SLAM systems, such as ORB-SLAM3 and LIFT-SLAM. These results underscore the efficacy and robustness of our DK-SLAM in varied and challenging real-world environments., Comment: In submission

The spectrum of the $c qq$ baryons contains a few states whose nature is not clearly a three-quark composite and which might have a sizable baryon-meson component. Examples include the $\Sigma_c(2800)$ or the $\Lambda_c(2940)$. Here we explore the spectrum of two-body systems composed of a light, octet baryon and a charmed meson (or antimeson) within a simple contact-range theory in which the couplings are saturated by light-meson exchanges. This results in the prediction of a series of composite anticharmed pentaquarks ($\bar{c} q qqq $) and singly-charmed baryons ($c \bar{q} qqq $). Among the later we find $J=\tfrac{1}{2}$ $\Xi D$ and $J=\tfrac{3}{2}$ $\Xi D^*$ bound states with masses matching those of the recently observed $\Omega_c(3185)$ and $\Omega_c(3327)$ baryons., Comment: 14 pages, 6 tables

The spectrum of the charmed meson-(anti)meson system is a fundamental tool for disentangling the nature of a few exotic hadrons, including the recently discovered $T_{cc}^+(3875)$ tetraquark, the $X(3960)$, or the $X(3872)$, the nature of which is still not clear after almost two decades of its discovery. Here we consider that the charmed meson-(anti)meson short-range interaction is described by the exchange of light-mesons ($\sigma$, $\rho$, $\omega$). The effects of light-meson exchanges are recast into a simple contact-range theory by means of a saturation procedure, resulting in a compact description of the two-hadron interaction. From this, if the $T_{cc}^+$ were to be an isoscalar $D^* D$ molecule, then there should exist an isoscalar $J=1$ $D^* D^*$ partner, as constrained by heavy-quark spin symmetry. Yet, within our model, the most attractive two charmed meson configurations are the isovector $J=0$ $D^* D^*$ molecule and its sextet $D_s^* D^*$ and $D_s^* D_s^*$ flavor partners. Finally, we find a tension between the molecular descriptions of the $T_{cc}^+$ and that of the $X(3872)$ and $X(3960)$, where most parameter choices suggest that if the $T_{cc}^+$ is purely molecular then the $X(3872)$ overbinds (or conversely, if the $X(3872)$ is a molecule the $T_{cc}^+$ does not bind). This might be consequential for determining the nature of these states., Comment: 13 pages, 4 tables

In this work, we interpret the newly observed $\eta_1(1855)$ resonance with exotic $J^{PC}=1^{-+}$ quantum numbers in the $I=0$ sector, reported by the BESIII Collaboration, as a dynamically generated state from the interaction between the lightest pseudoscalar mesons and axial-vector mesons. The interaction is derived from the lowest order chiral Lagrangian from which the Weinberg-Tomozawa term is obtained, describing the transition amplitudes among the relevant channels, which are then unitarized using the Bethe-Salpeter equation, according to the chiral unitary approach. We evaluate the $\eta_1(1855)$ decays into the $\eta\eta^{\prime}$ and $K\bar{K}^*\pi$ channels and find that the latter has a larger branching fraction. We also investigate its SU(3) partners, and according to our findings, the $\pi_1(1400)$ and $\pi_1(1600)$ structures may correspond to dynamically generated states, with the former one coupled mostly to the $b_1\pi$ component and the latter one coupled to the $K_1(1270)\bar{K}$ channel. In particular, our result for the ratio $\Gamma(\pi_1(1600)\to f_1(1285)\pi)/ \Gamma(\pi_1(1600)\to \eta^{\prime}\pi)$ is consistent with the measured value, which supports our interpretation for the higher $\pi_1$ state. We also report two poles with a mass about 1.7~GeV in the $I=1/2$ sector, which may be responsible for the $K^*(1680)$. We suggest searching for two additional $\eta_1$ exotic mesons with masses around 1.4 and 1.7~GeV. In particular, the predicted $\eta_1(1700)$ is expected to have a width around 0.1~GeV and can decay easily into $K\bar K\pi\pi$., Comment: Accepted for publication in Universe with a DOI link https://doi.org/10.3390/universe9020109

In this paper, a compact rejection filter is proposed based on 2.5-D spoof surface plasmon polariton (SSPP) structure and folded spilt-ring resonators (SRRs). By embedding the folded SRRs into periodic grooves of the 2.5-D SSPP transmission line, a rejection band is created in the ultra-wide passband, resulting in pass-rejection-pass frequency characteristics. The rejection band and the cut-off frequency of the filter can be adjusted independently by changing the geometrical parameters of the 2.5-D SSPP rejection unit. Because of the compact folding structure, the lateral size is reduced by 54% compared with the conventional 2-D SSPP rejection filter.

The nature of the $P_{c}(4312)$, $P_c(4440)$ and $P_c(4457)$ pentaquarks is a fascinating theoretical question. Within the molecular picture their more usual interpretation is that of $I=\tfrac{1}{2}$ $\bar{D} \Sigma_c$ and $\bar{D}^* \Sigma_c$ bound states. Here we argue in favor of interpreting the $P_c(4457)$ pentaquark as a $I=\tfrac{3}{2}$ $\bar{D}^* \Sigma_c$ bound state (with spin $J=\tfrac{1}{2}$) instead. Owing to isospin symmetry breaking effects, with this identification the partial decay width of the $P_c(4457)^+$ into $J/\psi p$ will be of the same order of magnitude as the $P_{c}(4312)^+$ and $P_c(4440)^+$, in contrast with the considerably larger partial decay width in the $I=\tfrac{1}{2}$ scenario. In turn, this leads to a different hidden-charm molecular pentaquark spectrum, in which there are only four or five $P_{\psi}^N$ bound states instead of the usual seven, which might explain why the predicted $J=\tfrac{1}{2}$ and $\tfrac{3}{2}$ ($I=\tfrac{1}{2}$) $\bar{D}^* \Sigma_c^*$ molecular partners of the $P_c(4312)$ and $P_c(4440)$ have not been observed., Comment: 6 pages, 2 tables

Theoretical predictions for the spectrum of heavy meson-baryon bound states are a fundamental tool for disentangling the nature of the different pentaquark states that have been observed in experimental facilities. Here we explore this spectrum in a phenomenological model that describes the heavy meson-baryon interaction in terms of a contact-range interaction, where the coupling strength is saturated by the exchange of light scalar and vector mesons, i.e. $\sigma$, $\rho$ and $\omega$ exchanges. Saturation determines the couplings modulo an unknown proportionality constant that can be calibrated from a molecular candidate. If we use the $P_{\psi}^N(4312)$ as input, we predict a series of molecular pentaquarks including the $P_{\psi}^N(4440)$ and $P_{\psi}^N(4457)$, the recent $P_{\psi s}^{\Lambda}(4338)$ and the $P_{\psi s}^{\Lambda}(4459)$., Comment: 8 pages, 3 tables

Starting from the hypothesis that the $T_{cc}^+$ discovered at LHCb is a $D^{\ast+} D^0/D^{\ast 0}D^+$ hadronic molecule, we consider the partial width of its heavy quark spin partner, the $T_{cc}^{\ast +}$ as a $D^{\ast +} D^{\ast 0}$ shallow bound state, decaying into the $D^{\ast}D\pi$ final states including the contributions of the $D^{\ast} D$ and $D^{\ast} \pi$ final state interaction by using a nonrelativistic effective field theory. Because of the existence of the $T_{cc}^+$ pole, the $I=0$ $D^{\ast} D$ rescattering can give a sizeable correction up to about $40\%$ to the decay widths considering only the tree diagrams, and the $D^{\ast} \pi$ rescattering correction is about $10\%$. The four-body partial widths of the $T_{cc}^{*+}$ into $D D\pi\pi$ are also explicitly calculated, and we find that the interference effect between different intermediate $D^*D\pi$ states is small. The total width of the $T_{cc}^{*+}$ is predicted to be about 41 keV., Comment: 31 pages, 10 figues. Results updated and extended, version to be published in Phys. Rev. D

Characterization and categorization of quantum correlations are both fundamentally and practically important in quantum information science. Although quantum correlations such as non-separability, steerability, and non-locality can be characterized by different theoretical models in different scenarios with either known (trusted) or unknown (untrusted) knowledge of the associated systems, such characterization sometimes lacks unambiguous to experimentalist. In this work, we propose the physical interpretation of nonlocal quantum correlation between two systems. In the absence of {\it complete local description} of one of the subsystems quantified by the {\it local uncertainty relation}, the correlation between subsystems becomes nonlocal. Remarkably, different nonlocal quantum correlations can be discriminated from a single uncertainty relation derived under local hidden state (LHS)-LHS model only. We experimentally characterize the two-qubit Werner state in different scenarios., Comment: 13 pages, 10 figures. Comments are welcome

Accurate and robust localization is a fundamental need for mobile agents. Visual-inertial odometry (VIO) algorithms exploit the information from camera and inertial sensors to estimate position and translation. Recent deep learning based VIO models attract attentions as they provide pose information in a data-driven way, without the need of designing hand-crafted algorithms. Existing learning based VIO models rely on recurrent models to fuse multimodal data and process sensor signal, which are hard to train and not efficient enough. We propose a novel learning based VIO framework with external memory attention that effectively and efficiently combines visual and inertial features for states estimation. Our proposed model is able to estimate pose accurately and robustly, even in challenging scenarios, e.g., on overcast days and water-filled ground , which are difficult for traditional VIO algorithms to extract visual features. Experiments validate that it outperforms both traditional and learning based VIO baselines in different scenes., Comment: Accepted by IEEE Sensors Journal

We investigate the $B^0\to \pi^- K^+ X(3872)$ decay via the $D_{s1}(2536)\bar{D} D^*$ rescattering diagram. The line shape of the $K^+X(3872)$ distribution curve around $D_{s1}(2536)\bar{D}$ threshold is very sensitive to the $X(3872)$ mass because the triangle singularity (TS) can be generated from the loop. By means of this characteristic, we can determine whether the $X(3872)$ mass is below or above the $D^{\ast 0}\bar{D}^0$ threshold with high precision. The narrowness of $D_{s1}(2536)$ in the loop is one of the key reasons why the TS mechanism of measuring the $X(3872)$ mass may work. The $X(3872)$ width impact on the $K^+X(3872)$ line shape is also crucial in the TS mechanism. If the width is as large as 1 MeV, the proposed method of measuring the $X(3872)$ mass would be ruined., Comment: 6 pages, 3 figures

The LHCb collaboration has detected a new hidden-charm pentaquark with the quantum numbers of a $\Lambda$ baryon: the $P_{\psi s}^{\Lambda}(4338)$. In the molecular picture this pentaquark will be interpreted as a $\bar{D} \Xi_c$ molecule. Here we briefly comment on the relation of the new $P_{\psi s}^{\Lambda}(4338)$ with the $P^{\Lambda}_{\psi s}(4459)$. We find that the $P_{\psi s}^{\Lambda}(4338)$ and $P_{\psi s}^{\Lambda}(4459)$ both accept a common molecular description in terms of the same parameters, which predicts the existence of a few additional $P_{\psi}^N$, $P_{\psi s}^{\Lambda}$, $P_{\psi s}^{\Sigma}$ and $P_{\psi s s}^{\Xi}$ pentaquarks composed of a charmed antimeson and an antitriplet charmed baryon. The most robust of these predicted pentaquarks is a $P_{\psi s}^{\Lambda}$ with a mass in the $(4235-4255)\,{\rm MeV}$ range, while other two interesting ones are a $P_{\psi}^{N}(4150)$ and a $P_{\psi}^{\Sigma}(4335)$, the later basically at the same mass as the $P_{\psi}^{\Lambda}(4338)$, with which it might mix owing to isospin symmetry breaking effects., Comment: 5 pages, 1 table

The heavy hadron spectrum is constrained by symmetries, of which two of the most important ones are heavy-quark spin and SU(3)-flavor symmetries. Here we argue that in the molecular picture the $Y(4230)$ (or $Y(4260)$), the $Y(4360)$ and the recently discovered $Y(4500)$ and $Y(4620)$ vector-like resonances are linked by these two symmetries. By formulating a contact-range effective field theory for the $D \bar{D}_1$ and $D_s \bar{D}_{s1}$ family of S- and P-wave charmed meson-antimeson systems, we find that if the $Y(4230)$ were to be a pure $D \bar{D}_1$ molecular state, there would be a $D^* \bar{D}_1$ partner with a mass similar to the $Y(4360)$, a $D_s \bar{D}_{s1}$ partner with a mass close to the $Y(4500)$ and three $J=1,2$ $D_s^* \bar{D}_{s1}$ and $J=3$ $D_s^* \bar{D}_{s2}^{*}$ bound states with a mass in the vicinity of $4630\,{\rm MeV}$, of which the first one ($J=1$) might correspond with the $Y(4620)$. The previous predictions can in turn be improved by modifying the assumptions we have used to build the effective field theory. In particular, if we consider the closeness of the $D^* \bar{D}_1$-$D^* \bar{D}_2^*$ and $D_s^* \bar{D}_{s1}$-$D_s^* \bar{D}_{s2}^*$ thresholds and include the related coupled channel dynamics, we predict a $J=2$ positive C-parity state with a mass around $4650\,{\rm MeV}$. This hidden-strange and hidden-charm state might in turn be identified with the $X(4630)$ that has been discovered past year by the LHCb in the $J/\psi \phi$ invariant mass distribution., Comment: 21 pages, 7 tables