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Among interesting applications of cold atoms, quantum simulations attract a lot of attention. In this context, rare-earth ultracold atoms are particularly appealing for such simulators due to their numerous Fano-Feshbach resonances and magnetic dipole moments in the ground state. However, creating a quantum gas microscope with these atoms presents challenges, primarily because of the need to transfer the atoms from the main cooling chamber to another chamber with large optical access. Stray magnetic fields complicate this transfer by exerting forces on the atoms. Using thulium atoms as an example, the study demonstrates that stray magnetic fields can be measured directly using the atoms themselves, allowing for these fields to be accounted for during the transfer process. This approach significantly improves the efficiency of the transfer, allowing to transfer over 1/3 of the atoms from the main chamber to the scientific chamber, located 56 cm away.

Adverse drug events (ADEs) significantly impact clinical research, causing many clinical trial failures. ADE prediction is key for developing safer medications and enhancing patient outcomes. To support this effort, we introduce CT-ADE, a dataset for multilabel predictive modeling of ADEs in monopharmacy treatments. CT-ADE integrates data from 2,497 unique drugs, encompassing 168,984 drug-ADE pairs extracted from clinical trials, annotated with patient and contextual information, and comprehensive ADE concepts standardized across multiple levels of the MedDRA ontology. Preliminary analyses with large language models (LLMs) achieved F1-scores up to 55.90%. Models using patient and contextual information showed F1-score improvements of 21%-38% over models using only chemical structure data. Our results highlight the importance of target population and treatment regimens in the predictive modeling of ADEs, offering greater performance gains than LLM domain specialization and scaling. CT-ADE provides an essential tool for researchers aiming to leverage artificial intelligence and machine learning to enhance patient safety and minimize the impact of ADEs on pharmaceutical research and development. The dataset is publicly accessible at https://github.com/ds4dh/CT-ADE.

Description of electrons as solitons of the polarization field implies that an ordinary dielectric has a hidden order, associated with the invariance with respect to adding loops of quantized electric flux. We describe the mechanism by which the finite polarizability of the medium renders the interaction between the solitons short-ranged (prior to their coupling to electromagnetism) and argue that the structure of the solitons allows them to be quantized as either fermions or bosons. At the quantum level, the theory has, in addition to the solitonic electric, elementary magnetic excitations, suggesting that small dielectrics may host quantized magnetic vortices carrying circular polarization currents., Comment: 7 pages, 4 figures

The number of atoms in Bose-Einstein condensate determines the scale of experiments that can be performed, making it crucial for quantum simulations. Optimization of the number of atoms in the condensate is a complex problem which could be efficiently solved using machine learning technique. Nevertheless, this approach usually does not give any insight in the underlying physics. Here we demonstrate possibility to learn physics from the machine learning on an example of condensation of thulium atoms at a 1064-nm dipole trap. Optimization of the number of condensed atoms revealed a saturation, which was explained as limitation imposed by a 3-body recombination process. This limitation was successfully overcome by leveraging Fano-Feshbach resonances.

A recent experiment has demonstrated formation of a supersonic region in a convergent two-dimensional flow of a condensate of cesium atoms. Theoretical description of this effect has made use of stationary solutions to the Gross-Pitaevskii equation with a 3-body dissipative term. Here, we further develop that description, focusing on a new stationary solution, linear stability analysis, and properties of the time-dependent "resistive" state., Comment: 5 pages, 4 figures; minor corrections, a slightly expanded version

Understanding the dynamics and stability of transonic flows in quantum fluids, especially for those beyond one spatial dimension, is an outstanding challenge, with applications ranging from nonlinear optics and condensed matter to analogue gravity. One intriguing possibility is that a system with a spatially bounded supersonic flow may evolve into a self-oscillating state that periodically emits solitons, in a process originating from the well-known Landau instability. Here, we report observation of self-oscillating supersonic flows in a two-dimensional atomic superfluid. By imposing a local particle sink with strong loss, we induce a convergent radial flow forming an acoustic analogue of a black-hole horizon and an inner horizon around the sink. The observed superflow appears to be modulated by quasi-periodic bursts of superluminal signals. We measure their frequencies and find agreement with numerical simulations of soliton oscillation frequencies within the black-hole horizon. The presented experiment demonstrates a new method for creating supersonic flows in atomic superfluids, which may find applications in quantum simulations of curved spacetime, supersonic turbulence, and self-oscillating dynamics in dissipative many-body systems., Comment: 9 pages, 6 figures

Recently, the thulium atom has been cooled down to the temperature of Bose-Einstein condensation. While the condensate of the thulium atom has a lot of applications in quantum simulations and other areas of physics, it can also serve as a unique diagnostic tool for many atomic experiments. In the present study, the Bose-Einstein condensate of the thulium atom was successfully utilized to diagnose an optical lattice and detect unwanted reflections in the experiments with the 1064 nm optical lattice, which will further be used in a quantum gas microscope experiment.

Recently thulium has been condensed to Bose-Einstein condensate. Machine learning was used to avoid a detailed study of all obstacles making cooling difficult. This paper analyses the atomic loss mechanism for the 532 nm optical trap, used in the Bose-condensation experiment, and compares it with the alternative and more traditional micron-range optical dipole trap. We also measured the scalar and tensor polarizability of thulium at 1064 nm and was found to be $167\pm 25$ a.u. ($275\pm 41\times {{10}^{-41}}\text{F }\cdot \text{ }{{\text{m}}^{\text{2}}}$) and $-4\pm 1$ a.u. ($7\pm 2\times {{10}^{-41}}\text{F }\cdot \text{ }{{\text{m}}^{\text{2}}}$).

Distinctive features of the created speech frame are: the ability to take into account the emotional state of the speaker, sup-port for working with diseases of the speech-forming tract of speakers and the presence of manual segmentation of a num-ber of speech signals. In addition, the system is focused on Russian-language speech material, unlike most analogs., Comment: 7 pages, 27 tables

We consider the theory of $N$ free Dirac fermions with a uniformly winding mass, $m e^{iqx}$, in two spacetime dimensions. This theory (which describes for instance a superconducting current in an $N$-channel wire) has been proposed to have a higher-spin gravity with scalar matter as the large-$N$ dual. To order $m^2$, however, thermodynamic quantities in it can be computed using standard general relativity instead. Here, we consider the question if the same is true for the entanglement entropy (EE). By comparing results obtained on two sides of the duality, we find that general relativity indeed accounts correctly for the EE of an interval to order $m^2$ (and all orders in $q$)., Comment: 15 pages, 1 figure

We report observation of quasiparticle pair-production and characterize quantum entanglement created by a modulational instability in an atomic superfluid. By quenching the atomic interaction to attractive and then back to weakly repulsive, we produce correlated quasiparticles and monitor their evolution in a superfluid through evaluating the in situ density noise power spectrum, which essentially measures a 'homodyne' interference between ground state atoms and quasiparticles of opposite momenta. We observe large amplitude growth in the power spectrum and subsequent coherent oscillations in a wide spatial frequency band within our resolution limit, demonstrating coherent quasiparticle generation and evolution. The spectrum is observed to oscillate below a quantum limit set by the Peres-Horodecki separability criterion of continuous-variable states, thereby confirming quantum entanglement between interaction quench-induced quasiparticles.

Recent studies demonstrated anomalous temperature shifts for some Fano-Feshbach resonances of thulium atoms. These anomalies were explained by the variation in light intensity in the optical dipole trap, which accompanied changes in temperature. In addition, a temperature-related transformation of the statistics of the interresonance spacing was demonstrated [1]. Here, we analyze the shifts of isolated s- and d-type Fano-Feshbach resonances of ultracold thulium atoms with temperature for a fixed depth of an optical dipole trap. The measurements are consistent with the 3-body recombination-based theory of the temperature-related resonance shift and enable the extraction of the resonance parameters, particularly the magnetic moments of closed channel states. This parameter and the known polarizability of the open channel enable us to separate the contributions of the temperature and Stark shift to the overall shift of the resonances and show the dominant role of the Stark effect in the overall shift.

Recently, transformation from random to chaotic behavior in the statistics of Fano-Feshbach resonances was observed in thulium atoms with rising ensemble temperature. We performed random matrix theory simulations of such spectra and analyzed the resulting statistics. Our simulations show that, when evaluated in terms of the Brody parameter, resonance statistics do not change or change insignificantly with rising temperature if temperature is the only changing parameter. In the experiments evaluated, temperature was changed simultaneously with optical dipole trap depth. Thus, simulations included the Stark shift based on the known polarizability of the free atoms and assuming their polarizability remains the same in the bound state. Somewhat surprisingly, we found that, while including the Stark shift does lead to minor statistical changes, it does not change the resonance statistics and, therefore, is not responsible for the experimentally observed statistic transformation. This observation suggests that either our assumption regarding the polarizability of Feshbach molecules is poor or that an additional mechanism changes the statistics and leads to more chaotic statistical behavior.

Recently, the thulium atom was cooled down to the Bose-Einstein condensation temperature, thus opening a pathway to quantum simulation with this atom. However, successful simulations require instruments to control and readout states of the atom as well as the ability to control the interaction between either different species or different states of the same type of species. In this paper, we provide an experimental demonstration of high-fidelity (over 93%) manipulation of the ground state magnetic sublevels of thulium, which utilizes a simple and efficient design of a microwave (MW) antenna. The coherence time and dephasing rate of the energetically highest hyperfine level of the ground state were also examined.

The rapid development of such natural language processing tasks as style transfer, paraphrase, and machine translation often calls for the use of semantic similarity metrics. In recent years a lot of methods to measure the semantic similarity of two short texts were developed. This paper provides a comprehensive analysis for more than a dozen of such methods. Using a new dataset of fourteen thousand sentence pairs human-labeled according to their semantic similarity, we demonstrate that none of the metrics widely used in the literature is close enough to human judgment in these tasks. A number of recently proposed metrics provide comparable results, yet Word Mover Distance is shown to be the most reasonable solution to measure semantic similarity in reformulated texts at the moment.

The differential cross sections of the $^{12}$C($^3$He,t)$^{12}$N reaction leading to formation of the 1$^+$ (ground state), 2$^+$(0.96 MeV), 2$^{-}$(1.19 MeV), and 1$^{-}$(1.80 MeV) states of $^{12}$N are measured at $E$($^3$He)=40 MeV. The analysis of the data is carried out within the modified diffraction model (MDM) and distorted wave Born approximation (DWBA). Enhanced $rms$ radii were obtained for the ground, 2$^{-}$(1.19 MeV), and 1$^{-}$(1.80 MeV) states. We revealed that $^{12}$B, $^{12}$N, and $^{12}$C in the IAS with T=1, and spin-parities 2$^{-}$ and 1$^{-}$ have increased radii and exhibit properties of neutron and proton halo states., Comment: 6 pages, 4 figures, 2 tables

Bose-Einstein condensation (BEC) is a powerful tool for a wide range of research activities, a large fraction of which are related to quantum simulations. Various problems may benefit from different atomic species, but cooling down novel species interesting for quantum simulations to BEC temperatures requires a substantial amount of optimization and is usually considered as a hard experimental task. In this work, we implemented the Bayesian machine learning technique to optimize the evaporative cooling of thulium atoms and achieved BEC in an optical dipole trap operating near 532 nm. The developed approach could be used to cool down other novel atomic species to quantum degeneracy without additional studies of their properties.

We consider decay of an initial density or current perturbation at finite temperature $T$ near a quantum critical point with emergent Lorentz invariance. We argue that decay of perturbations with wavenumbers $k \gg T$ (in natural units) is a good testing ground for holography---existence of a dual gravitational description---in experimentally accessible systems. The reason is that, computed holographically, the decay rate at large $k$ depends only on the leading correction to the metric near the boundary, and that is quite universal. In the limit of zero detuning (when the temperature is the only dimensionful parameter), the result is a scaling law for the decay rate, with the exponent that depends only on the dimensionality. We show that this follows from an analytical argument and is borne out by a numerical study of quasinormal modes., Comment: 5 pages, 2 figures; minor changes; references added

Entanglement entropy (EE) of a spatial region quantifies correlations between the region and its surroundings. For a free scalar in the adiabatic vacuum in de Sitter space the EE is known to remain low, scaling as the surface area of the region. Here, we study the evolution of entanglement after the universe transitions from de Sitter to flat space. We concentrate on the case of a massless minimally coupled scalar. We find numerically that, after the de Sitter stage ends, the EE and the R\'enyi entropy rapidly grow and saturate at values obeying the volume law. The final state of the subsystem (region) is a partially thermalized state reminiscent of a generalized Gibbs ensemble. We comment on application of our results to the question of when and how cosmological perturbations decohere., Comment: 15 pages, 3 figures; a typo corrected