Broken Phase Research Articles

Observation of Young’s double-slit phenomenon in anti-PT-symmetric electrical circuits

Abstract In the last few decades, interference has been extensively studied in both the quantum and classical fields, which reveals light volatility and is widely used for high-precision measurements. We have put forward the phenomenon in which the discrete diffraction and interference phenomena, presented by the time-varying voltage of a Su-Schrieffer-Heeger (SSH) circuit model with an anti-PT (APT) symmetry. To demonstrate Young’s double-slit phenomenon in an APT circuit, we initially explore the coupled mode theory (CMT) of voltage in the broken phase, observe discrete diffraction under single excitation and interference under double excitations. Furthermore, we design a phase-shifting circuit to observe the effects of phase difference and distance on discrete interference. Our work combines the effects in optics with condensed matter physics, show the Young’s double-slit phenomenon in electrical circuits theoretically and experimentally.

Clinical characteristics of a COVID-19 cohort treated at UCLA Ronald Reagan Medical Center during the breaking phase of the pandemic: A retrospective study

To this date, COVID-19 remains an unresolved pandemic, and the impairment of redox homeostasis dictates the severity of clinical outcomes. Here we examined initial UCLA cohort of 440 COVID-19 patients hospitalized between March 1st and April 1st, 2020, representing the first wave of the pandemic. The mean age was 58.88 ± 21.12, among which males were significantly more than females (55.5 % vs. 44.5 %), most distinctively in age group of 50–69. The age groups of 50–69 (33.6 %) and ≥70 (34.8 %) dominated. The racial composition was in general agreement with Census data with slight under-representation of Hispanics and Asians, and over-representation of Caucasians. Smoking was a significant factor (28.8 % vs. 11.0 % in LA population), likewise for obesity (BMI ≥30) (37.4 % vs. 27.7 % in LA population). Patients suffering from obesity or BMI<18.5 checked into ICU at a significantly higher rate. A 74.5 % of the patients had comorbidities including diabetes, chronic kidney disease, chronic pulmonary disease, congestive heart failure and peripheral vascular disease. The levels of d-dimer were drastically upregulated (1159.5 ng/mL), indicating hypercoagulative state. Upregulated LDH (328 IU/L) indicated significant tissue damages. A distorted redox hemeostasis is a common trait associated with these risk factors and clinical markers. A quarter of the patients received antivirals, among which Remdesivir most prescribed (23.6 %). Majority received antithrombotics (75 %), and antibiotics. Upon admission, 67 patients were intubated or received CPR; 177 patients eventually received intensive care (40.2 %). While 290 were discharged alive, 10 remained hospitalized, 73 were transferred, and 36 died with 3 palliatively discharged. In summary, our data fully characterized a Californian cohort of COVID-19 at the breaking phase of the pandemic, indicating that population demographics, biophysical characters, comorbidities and molecular pathological parameters have significant impacts on the evolvement of a pandemic. These provide critical insights into effective management of COVID-19, and future break from another pathogen.

Machine learning of knot topology in non-Hermitian band braids

The deep connection among braids, knots and topological physics has provided valuable insights into studying topological states in various physical systems. However, identifying distinct braid groups and knot topology embedded in non-Hermitian systems is challenging and requires significant efforts. Here, we demonstrate that an unsupervised learning with the representation basis of su(n) Lie algebra on n-fold extended non-Hermitian bands can fully classify braid group and knot topology therein, without requiring any prior mathematical knowledge or any pre-defined topological invariants. We demonstrate that the approach successfully identifies different topological elements, such as unlink, unknot, Hopf link, Solomon ring, trefoil, and so on, by employing generalized Gell-Mann matrices in non-Hermitian models with n=2 and n=3 energy bands. Moreover, since eigenstate information of non-Hermitian bands is incorporated in addition to eigenvalues, the approach distinguishes the different parity-time symmetry and breaking phases, recognizes the opposite chirality of braids and knots, and identifies out distinct topological phases that were overlooked before. Our study shows significant potential of machine learning in classification of knots, braid groups, and non-Hermitian topological phases.

Effective Abelian lattice gauge field theories for scalar-matter-monopole interactions

We present a gauge and Lorentz invariant effective field theory model for the interaction of a charged scalar matter field with a magnetic monopole source, described by an external magnetic current. The quantum fluctuations of the monopole field are described effectively by a strongly coupled “dual” Ud(1) gauge field, which is independent of the electromagnetic Uem(1) gauge field. The effective interactions of the charged matter with the monopole source are described by a gauge invariant mixed Chern-Simons-like (Pontryagin-density) term between the two U(1) gauge fields. The latter interaction coupling is left free, and a lattice study of the system is performed with the aim of determining the phase structure of this effective theory. Our study shows that, in the spontaneously broken-symmetry phase, the monopole source triggers, via the mixed Chern-Simons term, which is nontrivial in its presence, the generation of a dynamical singular configuration (magnetic-monopolelike) for the respective gauge fields. The scalar field also behaves in the broken phase in a way similar to that of the scalar sector of the ’t Hooft-Polyakov monopole. Moreover, we show that the modest size of the lattices involved does not have significant effects on the main conclusions of our analysis. Published by the American Physical Society 2024

Automatic Switching of Electric Locomotive Power in Railway Neutral Sections Using Image Processing.

This article presents a computer vision-based approach to switching electric locomotive power supplies as the vehicle approaches a railway neutral section. Neutral sections are defined as a phase break in which the objective is to separate two single-phase traction supplies on an overhead railway supply line. This separation prevents flashovers due to high voltages caused by the locomotives shorting both electrical phases. The typical system of switching traction supplies automatically employs the use of electro-mechanical relays and induction magnets. In this paper, an image classification approach is proposed to replace the conventional electro-mechanical system with two unique visual markers that represent the 'Open' and 'Close' signals to initiate the transition. When the computer vision model detects either marker, the vacuum circuit breakers inside the electrical locomotive will be triggered to their respective positions depending on the identified image. A Histogram of Oriented Gradient technique was implemented for feature extraction during the training phase and a Linear Support Vector Machine algorithm was trained for the target image classification. For the task of image segmentation, the Circular Hough Transform shape detection algorithm was employed to locate the markers in the captured images and provided cartesian plane coordinates for segmenting the Object of Interest. A signal marker classification accuracy of 94% with 75 objects per second was achieved using a Linear Support Vector Machine during the experimental testing phase.

Cosmic Strings from Thermal Inflation

Thermal inflation was proposed as a mechanism to dilute the density of cosmological moduli. Thermal inflation is driven by a complex scalar field possessing a large vacuum expectation value and a very flat potential, called a “flaton”. Such a model admits cosmic string solutions, and a network of such strings will inevitably form in the symmetry breaking phase transition at the end of the period of thermal inflation. We discuss the differences of these strings compared to the strings which form in the Abelian Higgs model. Specifically, we find that the upper bound on the symmetry breaking scale is parametrically lower than in the case of Abelian Higgs strings, and that the lower cutoff on the string loop distribution is determined by cusp annihilation rather than by gravitational radiation (for the value of the transition temperature proposed in the original work on thermal inflation).

Microstructure and Properties Evolution of 7075 Al alloy in Hot Rolling and Short Process Heat Treatment

7075 aluminum alloy is widely used in the aerospace field because of its low density, high specific strength, high fracture toughness, and good machinability. This paper systematically studied the evolution of the microstructure and properties of 7075 aluminum alloy at different temperatures. Based on the rolling and heat treatment process, a short process of rolling and heat treatment is proposed, which can significantly improve the properties. The study found that the nano‐phases were distributed in a “streamline‐like” or “lip‐like” shape after rolling. When the rolling temperature was below 550°C, the phases were mainly Al7Cu2Fe, the grain size did not change significantly, and shear bands appeared inside the grains. When rolled at 600°C, the grains coarsened significantly and the shear bands became longer, resulting in overburning and cracking. The broken phases were smoothed when rolled at 550°C. It was observed that the nano‐phases became larger. Due to the strain‐strengthening effect, the UTS increase by 6% with little change in elongation. In industrial production, direct aging treatment after high‐temperature rolling can reduce energy consumption and improve production efficiency.This article is protected by copyright. All rights reserved.

Bound states from the spectral Bethe-Salpeter equation

We compute the bound state properties of three-dimensional scalar ϕ4 theory in the broken phase. To this end, we extend the recently developed technique of spectral Dyson-Schwinger equations to solve the Bethe-Salpeter equation and determine the bound state spectrum. We employ consistent truncations for the two-, three- and four-point functions of the theory that recover the scaling properties in the infinite coupling limit. Our result for the mass of the lowest-lying bound state in this limit agrees very well with lattice determinations. Published by the American Physical Society 2024

An insight into the influence of precipitation phase on the surface quality in diamond turning of an Aluminium alloy

Diamond turning is an effective technology for processing metal mirrors used in photoelectric communications, radar, and other fields. In diamond turning, the precipitated phase is an essential factor that influences the surface quality of the metal mirrors. However, in previous studies, the precipitation phase has typically been handled as a random variable in a surface morphology model to evaluate its influence on the surface roughness, instead of determining the formation mechanism and proposing suppression solutions. In this study, a new phenomenon is observed in the diamond turning of metal mirrors, that is, the micro diamond tool can reduce the protrusion of the precipitated phase under a small feed rate and improve the surface quality. Investigating the turning process using diamond tools with varying tool nose radii at small feed rates (<1 μm/r), the underlying transformation mechanism of the precipitation phase is determined with the advanced material characterization technologies. The growth of the precipitated phase with an increase in the tool nose radius is explained using the energy gradient theory. The results showed that the increased material strain on the machined surface decreased the activation energy of solute diffusion in the material, causing solute accumulation and precipitate phase growth. With a further increase of tool nose radius to around 1000 μm, the β'' phase breaks and rotates. The representative volume element method shows that when undergoing severe plastic deformation, dislocations and grain boundaries quickly aggregate and slide on the precipitated phase, which will lead to the fracture and rotation of β'' phase. These findings provide a theoretical basis for the development of highly smooth mirrors.

Percolating cosmic string loops from evaporating primordial black holes

The Pulsar timing data from NANOGrav Collaboration has regenerated interest in the possibility of observing stochastic gravitational wave background arising from cosmic strings. Standard theory of formation of cosmic strings is based on a spontaneous symmetry breaking (SSB) phase transition in the early universe, with a string network forming via the so called Kibble mechanism. This string network rapidly evolves and reaches a scaling solution with a given spectrum of string loops and long strings at any given time. This scenario necessarily requires that the entire observable Universe goes through the SSB phase transition. This would not be possible, e.g., in models of low energy inflation, where the reheat temperature is much lower than the energy scale of cosmic strings. We point out a very different possibility, where a network of even high energy scale cosmic strings can form when the temperature of the Universe is much lower. We consider local heating of plasma in the early universe by evaporating primordial black holes (PBHs). It is known that for suitable masses of PBHs, Hawking radiation of evaporating primordial black holes may re-heat the surrounding plasma to high temperatures, restoring certain symmetries locally which are broken at the ambient temperature of the Universe at that stage. Expansion of the hot plasma cools it so that the locally restored symmetry is spontaneously broken again. If this SSB supports formation of cosmic strings, then string loops will form in this region around the PBH. Further, resulting temperature gradients lead to large pressure gradients such that plasma will develop radial flow with the string loops getting stretched as they get dragged by the flow. For a finite density of PBHs of suitable masses, one will get local hot spots, each one contributing to expanding cosmic string loops. For suitable PBH density, the loops from different regions may intersect. If that happens, then intercommutation of strings can lead to percolation, leading to the possibility of formation of infinite string network, even when the entire universe never goes through the respective SSB phase transition.

Non-uniform microstructure evolution rules and mechanisms of Ti55 alloy with initial basket-weave structure during electrically-assisted V bending

Electrically assisted V-bending (EAVB) experiments of Ti55 alloy sheets with initial basketweave structure were carried out at effective current densities of 3–5A/mm2. The history of temperature field, microstructure patterns and mechanical properties were characterized by IR imaging, OM, EBSD and hardness tests. The results show that α lamellae continuously decrease in thickness (from 2.38 μm to 0.64 μm) with increasing current density. The microstructure patterns of the three deformation zones are significantly different due to different deformation mode and electro-thermo-mechanical routes. Due to limited plastic strain, the orientation rotation and shear fracture of the α lamellae are restricted in the neutral layer, while the ones in the inner and outer layers are refined and become more uniform at mild current density. With increasing current density, the main deformation mode of α grains in the inner layer is {1010} prismatic slip and dynamic spheroidization/recrystallization tends to occur at α lamellae with <0110>α//TD orientation. In the neural and outer layer, intense local Joule heat effect induces α→β→α′ phase transformation in “hot spots”, leading to massive growth of 3 variant needle-like α′, intensified heterogeneous micro-deformation and significant strengthening effect. The combined effects of local Joule heat, residual α phase and deformation-induced defect nucleation break the strict Burgers orientation relationship between α/α’ lamellae and β matrix during EAVB and subsequent cooling process.

Deformation mode and strengthening mechanism of Mg-Gd-Er-Zn-Zr alloy with different LPSO morphology

Figuring out the effects of LPSO morphology on the deformation mode and strengthening mechanism of Mg-RE alloys is helpful to improve their formability and mechanical properties. In this work, the Mg-8Gd-1Er-1Zn-0.6Zr (GEZ811) alloys with monolithic block LPSO (B-alloy) and lamellar LPSO (L-alloy) phase were respectively prepared by different heat treatment route. The effects of the monolithic LPSO morphology on deformation mode and strengthening mechanisms during high strain rate multidirectional forging (HSMDF) were analyzed. Results showed at the initial stage of HSMDF, twinning was the dominant deformation mode for B-alloy while non-basal slip was for L-alloy. With increasing forging pass, kink band of grains became primary for B-alloy, whereas kinking and breaking of the lamellar LPSO phase was dominant for L-alloy. The optimal UTS, YS and EL of the HSMDFed B-alloy and L-alloy at 12 P were 381.6 MPa, 324.1 MPa, and 8.8 %, and 358.4 MPa, 295.0 MPa, and 5.5 %, respectively. The difference in strength between B-alloy and L-alloy resulted primarily from the contribution of grain boundary strengthening and stacking fault strengthening, while the better plasticity of B-alloy was attributed to its lower deformation activation energy and the formed kink band of grains. Retaining the block LPSO phase as much as possible in the alloy before deformation is beneficial to enhancing the mechanical performance of Mg-RE alloys.

Type-II Dirac phonons in a two-dimensional phononic crystal

We explore the distinctive properties associated with a type-II Dirac point in a simply structured phononic crystal with a lattice deformation. This type-II Dirac point emerges at the Brillouin zone boundary, resulting from the lifting of two degenerate bands and featuring a conical-like Fermi surface in the equi-frequency curve. A practical implementation of such a phononic crystal is achieved with LEGO bricks. Upon introducing a periodic parity-time (PT) symmetric non-Hermitian perturbation, the phononic crystal undergoes a transition from PT-symmetric phase to PT-broken phase, causing the deformation of type-II Dirac point into an oval of exceptional points in the band structure. Based on the eigenmodes of the type-II Dirac point, a k⃗⋅p⃗ perturbation theory can be used to characterize these systems before and after the phase transition. Using a scattering matrix, we analyze the symmetric and broken phases and demonstrate that broadband unidirectional transparency and a coherent perfect absorber and laser can be realized with such a phononic crystal slab.

Electronic Raman response of a superconductor across a time reversal symmetry breaking phase transition

Electronic Raman response of a superconductor across a time reversal symmetry breaking phase transition

Acute Effects of Countermovement Jumps with Post-activation Potentiation Utilizing Additional Elastic Resistance during Eccentric Stretching Phase

&lt;p&gt;目的：本研究欲探究下蹲階段輔以彈性阻力之反向跳預先活動，對於6分鐘恢復時間後之跳躍表現的活化後增益效應。方法：本研究招募11名國立大學體育相關科系男性學生為受試對象，施以2循環、每循環5次的反向跳預先活動，且於下蹲制動階段介入外加彈性阻力，阻力強度分為0% BW、15% BW、30% BW三種情境，並於預先活動介入前與介入後第6分鐘後進行前測與後測。以兩塊測力板擷取前測與後測之反向跳過程中垂直地面反作用力值與時間，並計算發力率、跳躍高度、修正式反應力量指標以及下肢勁度。以相依樣本 t-test 進行統計檢驗，統計水準訂為 &amp;alpha; = .05，比較前測與後測的下肢動態力量特徵之參數是否有差異。結果：本研究結果顯示，三種介入模式皆顯著提升反向跳制動末點力值 (p &lt; .05)。15% BW與30% BW的介入模式顯著提升制動期與推蹬期發力率 (p &lt; .05)。30 % BW的介入模式顯著提升反向跳下肢勁度、修正式反應力量指標，並縮短制動期時間 (p &lt; .05)。結論：本研究之介入應有助於增進牽張反射機制之效益，尤其是在離心制動階段的肌力特徵表現上，因此，建議在進行具備牽張反射機制之動作執行前，可透過反向跳下蹲階段輔以30% BW彈性阻力進行下肢動態肌力活化之預先活動，以助於後續之運動表現。&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;Purpose: The current study aimed at exploring the immediate effect of pre-activities of countermovement jumps, with elastic resistance and 6 minutes of recovery time, on post-activation potentiation during squatting phase. Method: Eleven male college students recruited from the Physical Education department at National Dong Hwa University were asked to perform pre-activities of countermovement jumps (2 cycles, 5 repetitions for each cycle), with elastic resistances (0% BW, 15% BW, and 30% BW) during the squatting phase, followed by pre-tests and post-tests before and after six minutes of recovery time. Two AMTI force plates were used to collect data on vertical ground reaction force and time during countermovement jumps for pre- and post-tests. Rate of force development, jump heights, reactive strength index modified, and lower extremity stiffness were calculated accordingly. Dependent sample t-test was conducted (&amp;alpha;=.05) to determine if there were significant differences in the parameters related to lower extremity dynamic strength between the pre- and post-tests. Results: Pre-activities with all three interventions significantly increased the ground reaction forces during the breaking phase (p &lt; .05). Pre-activities with elastic resistances of 15% and 30% BW significantly elevated the rates of force development during the breaking and propulsive phases (p &lt; .05). Pre-activities with 30% BW elastic resistance significantly led to increased lower extremity stiffness, reactive strength index modified, and decreased breaking time (p &lt; .05). Conclusion: The added elastic resistance enhanced the benefits of stretch reflex mechanism, especially the muscle strength characteristics during the eccentric breaking phase. Based on our finding, countermovement jumps with pre-activity with elastic resistance of 30% BW is recommended prior to performing movements concerning stretch reflex mechanism.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Bacterial community changes in strawberry fruits (Fragaria × ananassa variety "Monterey") from farm field to retail market stands, an indicator of postharvest contamination.

Strawberry (Fragaria × ananassa) fruits are vulnerable to bacterial contamination; some species are pathogenic and can affect human health. Comprehending the bacterial composition and diversity at different ripe stages is a key determinant of the fruit health, productivity, and quality. An amplicon metagenomic approach on the 16S rRNA region was used to identify the bacterial diversity in exocarp of fruits collected from a farm field at two ripe stages: breaking (white, phase two) and ripe (red, phase four) and purchased from different retail market stands at ripe (red, phase four, ready-to-eat) stage. Besides, the fruit quality was assessed. Strawberries carries a high microorganisms diversity, with Pseudomonaceae, Yearsiniaceae, and Hafniaceae being the most abundant families across the samples. Among the groups, Pseudomonaceae and Clostridiaceae were the most abundant families at breaking (phase two) and ripe (phase four), whereas Yearsiniaceae, Hafniaceae, Aeromonadaceae, and Streptococcaceae were the most abundant families in the market group. Although samples from group four-field and market were at the same ripe stage, the bacterial species composition was divergent. Serratia spp. were prevalent (above 60%) in samples collected from the market group, and Pseudomonas (above 70%) species were mostly found in the samples collected from the field settings regardless of the phase. Besides, Escherichia coli and Salmonella enterica were detected in the ready-to-eat samples from both the field and the market, while Enterococcus gallinarum was detected in the samples that originated from the market. Interestingly, Shewanella putrefaciens and Shewanella profunda, two human opportunistic pathogens, were detected in the fruits from the market only. According to alpha and beta diversity analyses, strawberry fruits displayed significant differences (P < 0.05) in bacterial communities within the ripe group, with the samples from the market showing the most bacterial diversity. Although we do not directly correlate the quality attributes with bacterial diversity, the results indicated a clear separation between groups according with their ripe stage and origin. This study provides a comprehensive framework of the bacterial diversity throughout the transition from unripe to ripe strawberries which may aid in the development of preventative measures to manage the postharvest contamination.

A High Working Temperature Multiferroic Induced by Inverse Temperature Symmetry Breaking.

Molecular-based multiferroic materials that possess ferroelectric and ferroelastic orders simultaneously have attracted tremendous attention for their potential applications in multiple-state memory devices, molecular switches, and information storage systems. However, it is still a great challenge to effectively construct novel molecular-based multiferroic materials with multifunctionalities. Generally, the structure of these materials possess high symmetry at high temperatures, while processing an obvious order-disorder or displacement-type ferroelastic or ferroelectric phase transition triggered by symmetry breaking during the cooling processes. Therefore, these materials can only function below the Curie temperature (Tc), the low of which is a severe impediment to their practical application. Despite great efforts to elevate Tc, designing single-phase crystalline materials that exhibit multiferroic orders above room temperature remains a challenge. Here, an inverse temperature symmetry-breaking phenomenon was achieved in [FPM][Fe3(μ3-O)(μ-O2CH)8] (FPM stands for 3-(3-formylamino-propyl)-3,4,5,6-tetrahydropyrimidin-1-ium, which acts as the counterions and the rotor component in the network), enabling a ferroelastoelectric phase at a temperature higher than Tc (365 K). Upon heating from room temperature, two-step distinct symmetry breaking with the mm2Fm species leads to the coexistence of ferroelasticity and ferroelectricity in the temperature interval of 365-426 K. In the first step, the FPM cations undergo a conformational flip-induced inverse temperature symmetry breaking; in the second step, a typical ordered-disordered motion-induced symmetry breaking phase transition can be observed, and the abnormal inverse temperature symmetry breaking is unprecedented. Except for the multistep ferroelectric and ferroelastic switching, this complex also exhibits fascinating nonlinear optical switching properties. These discoveries not only signify an important step in designing novel molecular-based multiferroic materials with high working temperatures, but also inspire their multifunctional applications such as multistep switches.

Probing exotic phases via stochastic gravitational wave spectra

Abstract Stochastic backgrounds of gravitational waves (GWs) from the pre-BBN era offer a unique opportunity to probe the universe beyond what has already been achieved with the Cosmic Microwave Background (CMB). If the source is short in duration, the low frequency tail of the resulting GW spectrum follows a universal frequency scaling dependent on the equation of state of the universe when modes enter the horizon. We demonstrate that the distortion of the equation of state due to massive particles becoming non-relativistic can lead to an observable dip in the GW spectrum. To illustrate this effect, we consider a first order chiral symmetry breaking phase transition in the weak-confined Standard Model (WCSM). The model features a large number of pions and mostly elementary fermions with masses just below the critical temperature for the phase transition. These states lead to a 20% dip in the GW power. We find potential sensitivity to the distortions in the spectrum to future GW detectors such as LISA, DECIGO, BBO, and μAres.

Tunable single frequency Hz-magnitude narrow linewidth Brillouin fiber laser based on parity-time symmetry.

An Hz-magnitude ultra-narrow linewidth single-frequency Brillouin fiber laser (BFL) is proposed and experimentally demonstrated. The single frequency of the laser is selected by parity-time (PT) symmetry, which consists of a stimulated Brillouin scatter (SBS) gain path excited by a 24 km single-mode fiber (SMF) and an approximately equal length loss path tuned with a variable optical attenuator (VOA). These paths are coupled through a fiber Bragg grating (FBG) into a wavelength space. Accomplishing single-frequency oscillation involves the precise adjustment of polarization control (PC) and VOA to attain the PT broken phase. In the experiment, the linewidth of the proposed BFL is 9.58 Hz. The optical signal-to-noise ratio (OSNR) reached 78.89 dB, with wavelength and power fluctuations of less than 1pm and 0.02 dB within one hour. Furthermore, the wavelength can be tuned from 1549.9321 nm to 1550.2575 nm, with a linewidth fluctuation of 1.81 Hz. The relative intensity noise (RIN) is below -74 dB/Hz. The proposed ultra-narrow single-frequency BFL offers advantages such as cost-effectiveness, ease of control, high stability and excellent output characteristics, making it highly promising for the applications in the coherent detection.

Heteronuclear Magnetisms with Ultracold Spinor Bosonic Gases in Optical Lattices

Motivated by recent realizations of spin-1 NaRb mixtures in the experiments [Phys. Rev. Lett. 114, 255301 (2015); Phys. Rev. Lett. 128, 223201 (2022)], we investigate heteronuclear magnetism in the Mott-insulating regime. Different from the identical mixtures where the boson statistics only admits even parity states from angular momentum composition, for heteronuclear atoms in principle all angular momentum states are allowed, which can give rise to new magnetic phases. While various magnetic phases can be developed over these degenerate spaces, the concrete symmetry breaking phases depend on not only the degree of degeneracy but also the competitions from many-body interactions. We unveil these rich phases using the bosonic dynamical mean-field theory approach. These phases are characterized by various orders, including spontaneous magnetization order, spin magnitude order, singlet pairing order, and nematic order, which may coexist specially in the regime with odd parity. Finally we address the possible parameter regimes for observing these spin-ordered Mott phases.