Showing papers on "Quadrupole published in 2022"
48 citations
TL;DR: In this article , the authors investigated the sensitivity of the LISA to the anisotropies of the Stochastic Gravitational Wave Background (SGWB) with a power-law frequency profile.
Abstract: We investigate the sensitivity of the Laser Interferometer Space Antenna (LISA) to the anisotropies of the Stochastic Gravitational Wave Background (SGWB). We first discuss the main astrophysical and cosmological sources of SGWB which are characterized by anisotropies in the GW energy density, and we build a Signal-to-Noise estimator to quantify the sensitivity of LISA to different multipoles. We then perform a Fisher matrix analysis of the prospects of detectability of anisotropic features with LISA for individual multipoles, focusing on a SGWB with a power-law frequency profile. We compute the noise angular spectrum taking into account the specific scan strategy of the LISA detector. We analyze the case of the kinematic dipole and quadrupole generated by Doppler boosting an isotropic SGWB. We find that β ΩGW ∼ 2 × 10-11 is required to observe a dipolar signal with LISA. The detector response to the quadrupole has a factor ∼ 103 β relative to that of the dipole. The characterization of the anisotropies, both from a theoretical perspective and from a map-making point of view, allows us to extract information that can be used to understand the origin of the SGWB, and to discriminate among distinct superimposed SGWB sources.
46 citations
TL;DR: In this article , the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc) with the density functional PC-PK1 was used to calculate the ground state properties of even-even nuclei with 8≤Z≤120 from the proton drip line to the neutron drip line.
44 citations
TL;DR: In this article , a theoretical framework for all-order plasmonically induced transparency (PIT) was proposed, where the additional resonant phase of one mode over the other was defined as phase difference, which predicts that the PIT effects appear (disappear) generally near the positions where the phase difference is around odd (even) multiple numbers of π.
Abstract: Due to its transparent and highly dispersive nature, plasmonically induced transparency (PIT) has become an attractive field in the on-chip control of light. Conventional methods to achieve PIT are only limited to the lowest dipole-dipole or dipole-combined quadrupole modes by breaking structural symmetry. Consequently, a general methodological framework for accurately designing all-order PIT remains absent. In this paper, we propose a theoretical scheme to achieve unidirectional odd-to-even order PIT by establishing a model with two layers of periodic graphene nanoribbons. The underlying physical principles are uncovered by defining the additional resonant phase of one mode over the other as phase difference, which predicts that the PIT effects appear (disappear) generally near the positions where the phase difference is around odd (even) multiple numbers of \ensuremath{\pi}. Full-wave simulations and theoretical analysis are used to demonstrate our proposal, revealing that the proposed PIT concept possesses good robustness against both the ribbon width and the relative ribbon positions. Our results serve to provide an effective method to realize all-order PIT and to design PIT-based photonic devices.
37 citations
TL;DR: In this article , the authors investigated the structure of the charge density wave (CDW) order in kagome-metal superconductors and found that the CDW order is commensurate with the charge modulation.
Abstract: $A$V$_3$Sb$_5$ ($A$ = K, Rb, Cs) is a novel kagome superconductor coexisting with the charge density wave (CDW) order. Identifying the structure of the CDW order is crucial for understanding the exotic normal state and superconductivity in this system. Here, we report $^{51}$V nuclear magnetic resonance (NMR) and $^{121/123}$Sb nuclear quadrupole resonance (NQR) studies on kagome-metal CsV$_3$Sb$_5$. Below the CDW transition temperature $T_\textrm{CDW} \sim$ 98 K, an abrupt change of spectra was observed, indicating that the transition is of the first order. By further analysing the spectra, we find that the CDW order is commensurate. And most remarkably, the obtained experimental results suggest that the charge modulation of the CDW order is of star-of-David pattern and accompanied by an additional charge modulation in bulk below $T^* \sim$ 40 K. Our results revealing the unconventional CDW order provide new insights into $A$V$_3$Sb$_5$.
34 citations
TL;DR: In this paper , it was shown that the octupole correlations in the ground state of isobaric heavy-ion collisions are a natural consequence of the quadrupole deformation and octupoles deformation of colliding nuclei.
Abstract: In the hydrodynamic model description of heavy-ion collisions, the elliptic flow v_{2} and triangular flow v_{3} are sensitive to the quadrupole deformation β_{2} and octupole deformation β_{3} of the colliding nuclei. The relations between v_{n} and β_{n} have recently been clarified and were found to follow a simple parametric form. The STAR Collaboration has just published precision v_{n} data from isobaric ^{96}Ru+^{96}Ru and ^{96}Zr+^{96}Zr collisions, where they observe large differences in central collisions v_{2,Ru}>v_{2,Zr} and v_{3,Ru}
27 citations
TL;DR: In this article , the authors derived the tail and non-linear memory terms associated with the dipole radiation in massless scalar-tensor (ST) theories and derived the multipole moments and GW flux of compact binary systems for general orbits including the new 1.5PN contribution.
Abstract: We compute the gravitational waves generated by compact binary systems in a class of massless scalar-tensor (ST) theories to the 1.5 post-Newtonian (1.5PN) order beyond the standard quadrupole radiation in general relativity (GR). Using and adapting to ST theories the multipolar-post-Minkowskian and post-Newtonian formalisms originally defined in GR, we obtain the tail and non-linear memory terms associated with the dipole radiation in ST theory. The multipole moments and GW flux of compact binaries are derived for general orbits including the new 1.5PN contribution, and comparison is made with previous results in the literature. In the case of quasi-circular orbits, we present ready-to-use templates for the data analysis of detectors, and for the first time the scalar GW modes for comparisons with numerical relativity results.
21 citations
29 Apr 2022
TL;DR: In this paper , the authors consistently couple simple continuum field theories with fracton excitations to curved spacetime backgrounds, and obtain the respective Ward identities for fracton field theory with conserved U(1) charge and dipole moment.
Abstract: We consistently couple simple continuum field theories with fracton excitations to curved spacetime backgrounds. We consider homogeneous and isotropic fracton field theories, with a conserved U(1) charge and dipole moment. Coupling to background fields allows us to consistently define a stress-energy tensor for these theories and obtain the respective Ward identities. Along the way, we find evidence for a mixed gauge-gravitational anomaly in the symmetric tensor gauge theory which naturally couples to conserved dipoles. Our results generalise to systems with arbitrarily higher conserved moments, in particular, a conserved quadrupole moment.
19 citations
TL;DR: In this paper , the authors conducted relativistic simulations in a class of scalar-tensor theories with derivative self-interactions and screening of local scales and found that screening tends to suppress the (subdominant) dipole scalar emission, but not the dominant quadrupole scaling mode.
Abstract: We have conducted fully relativistic simulations in a class of scalar-tensor theories with derivative self-interactions and screening of local scales. By using high-resolution shock-capturing methods and a nonvanishing shift vector, we have managed to avoid issues plaguing similar attempts in the past. We have first confirmed recent results by ourselves in spherical symmetry, obtained with an approximate approach and pointing at a partial breakdown of the screening in black-hole collapse. Then, we considered the late inspiral and merger of binary neutron stars. We found that screening tends to suppress the (subdominant) dipole scalar emission, but not the (dominant) quadrupole scalar mode. Our results point at quadrupole scalar signals as large as (or even larger than) in Fierz-Jordan-Brans-Dicke theories with the same conformal coupling, for strong-coupling scales in the MeV range that we can simulate.
19 citations
TL;DR: In this article , the Glauber model was used to measure the collective flow response of the produced quark-gluon plasma to the eccentricity and the density gradient in high-energy heavy ion collisions.
Abstract: Most atomic nuclei are deformed with a quadrupole shape described by its overall strength $\beta_2$ and triaxiality $\gamma$. The deformation can be accessed in high-energy heavy-ion collisions by measuring the collective flow response of the produced quark-gluon plasma to the eccentricity $\varepsilon_2$ and the density gradient $d_{\perp}$ in the initial state. Using analytical estimate and a Glauber model, I show that the variances, $\langle\varepsilon_2^2\rangle$ or $\langle(\delta d_{\perp}/d_{\perp})^2\rangle$, and skewnesses, $\langle\varepsilon_2^2\delta d_{\perp}/d_{\perp}\rangle$ or $\langle(\delta d_{\perp}/d_{\perp})^3\rangle$, have a simple analytical form of $a'+b'\beta_2^2$ and $a'+(b'+c'\cos(3\gamma))\beta_2^3$, respectively. From these, I constructed several normalized skewnesses to isolate the $\gamma$ dependence from that of $\beta_2$, and show that the correlations between any normalized skewness and any variance can constrain simultaneously the $\beta_2$ and $\gamma$. Assuming a linear relation with elliptic flow $v_2$ and mean-transverse momentum $[p_{\mathrm{T}}]$ of final state particles, similar conclusions are also expected for the variances and skewnesses of $v_2$ and $[p_{\mathrm{T}}]$. Our findings motivate a dedicated system scan of high-energy heavy ion collisions to measure triaxiality of atomic nuclei. This is better done by collisions of prolate, $\cos(3\gamma)=1$, and oblate nuclei, $\cos(3\gamma)=-1$, with well known $\beta_2$ values to calibrate the coefficients $b'$ and $c'$, followed by collisions of species of interest especially those with known $\beta_2$ but unknown $\gamma$. The results demonstrate the unique opportunities offered by high-energy collisions as a tool to perform interdisciplinary nuclear physics studies.
19 citations
University of Pisa1, University of Florida2, University of Sannio3, Max Planck Society4, INFN Sezione di Roma I5, Université Paris-Saclay6, University of Sassari7, University of Sheffield8, École Normale Supérieure9, University of Valencia10, Scottish Universities Physics Alliance11, Russian Quantum Center12, ARC Centre of Excellence for Gravitational Wave Discovery13, Osaka Institute of Technology14, California Institute of Technology15, University of Grenoble16, University of Wisconsin–Milwaukee17, National Dairy Research Institute18, European Gravitational Observatory19, University of Orléans20, University of Glasgow21, National Security Technologies (United States)22, University of Georgia23, Nordic Optical Telescope24, University of British Columbia25, Aston University26, University of Portsmouth27, Chung-Ang University Hospital28
TL;DR: In this article , a targeted search for continuous gravitational waves (GWs) from 236 pulsars using data from the third observing run of LIGO and Virgo (O3) combined with data from O2.
Abstract: We present a targeted search for continuous gravitational waves (GWs) from 236 pulsars using data from the third observing run of LIGO and Virgo (O3) combined with data from the second observing run (O2). Searches were for emission from the $l=m=2$ mass quadrupole mode with a frequency at only twice the pulsar rotation frequency (single harmonic) and the $l=2, m=1,2$ modes with a frequency of both once and twice the rotation frequency (dual harmonic). No evidence of GWs was found so we present 95\% credible upper limits on the strain amplitudes $h_0$ for the single harmonic search along with limits on the pulsars' mass quadrupole moments $Q_{22}$ and ellipticities $\varepsilon$. Of the pulsars studied, 23 have strain amplitudes that are lower than the limits calculated from their electromagnetically measured spin-down rates. These pulsars include the millisecond pulsars J0437\textminus4715 and J0711\textminus6830 which have spin-down ratios of 0.87 and 0.57 respectively. For nine pulsars, their spin-down limits have been surpassed for the first time. For the Crab and Vela pulsars our limits are factors of $\sim 100$ and $\sim 20$ more constraining than their spin-down limits, respectively. For the dual harmonic searches, new limits are placed on the strain amplitudes $C_{21}$ and $C_{22}$. For 23 pulsars we also present limits on the emission amplitude assuming dipole radiation as predicted by Brans-Dicke theory.
TL;DR: In this paper , it was shown that the unconventional superconductor CeRh{}_{2}$As${}_{ 2]$As{}{ 2}$ may host a quadrurupole density wave, a theorized complex ordering pattern among free electrons that has not yet been observed.
Abstract: Experiments show that the unconventional superconductor CeRh${}_{2}$As${}_{2}$ may host a ``quadrupole density wave''---a theorized complex ordering pattern among free electrons that has not yet been observed.
TL;DR: In this article , the Pearson correlation coefficient between elliptic flow and radial flow was found to be particularly sensitive to the quadrupole deformation parameter, which is traditionally measured in low energy experiments.
Abstract: In heavy ion collisions, elliptic flow $v_2$ and radial flow, characterized by event-wise average transverse momentum $[p_{\mathrm{T}}]$, are related to the shape and size of the overlap region, which are sensitive to the shape of colliding atomic nuclei. The Pearson correlation coefficient between $v_2$ and $[p_{\mathrm{T}}]$, $\rho_2$, was found to be particularly sensitive to the quadrupole deformation parameter $\beta$ that is traditionally measured in low energy experiments. Built on earlier insight that the prolate deformation $\beta>0$ reduces the $\rho_2$ in ultra-central collisions (UCC), we show that the prolate deformation $\beta<0$ enhances the value of $\rho_2$. As $\beta>0$ and $\beta<0$ are the two extremes of triaxiality, the strength and sign of $v_2^2-[p_{\mathrm{T}}]$ correlation can be used to provide valuable information on the triaxiality of the nucleus. Our study provide further arguments for using the hydrodynamic flow as a precision tool to directly image the deformation of the atomic nuclei at extremely short time scale ($<10^{-24}$s).
TL;DR: In this article , it was shown that negatively charged boron vacancies (VB-) in hexagonal borsnide (hBN) meet the prerequisites for coherent coupling of defect spins with surrounding nuclei along with the endowment to read out the latter.
Abstract: Coherent coupling of defect spins with surrounding nuclei along with the endowment to read out the latter are basic requirements for an application in quantum technologies. We show that negatively charged boron vacancies (VB-) in hexagonal boron nitride (hBN) meet these prerequisites. We demonstrate Hahn-echo coherence of the VB- spin with a characteristic decay time Tcoh = 15 μs, close to the theoretically predicted limit of 18 μs for defects in hBN. Elongation of the coherence time up to 36 μs is demonstrated by means of the Carr-Purcell-Meiboom-Gill decoupling technique. Modulation of the Hahn-echo decay is shown to be induced by coherent coupling of the VB- spin with the three nearest 14N nuclei via a nuclear quadrupole interaction of 2.11 MHz. DFT calculation confirms that the electron-nuclear coupling is confined to the defective layer and stays almost unchanged with a transition from the bulk to the single layer.
TL;DR: In this paper , a regular pattern, revealing the leading role of the light-fragment nuclear charge, is found from a consistent analysis of the experimental information collected recently on low-energy asymmetric fission of neutron-deficient nuclei around lead.
TL;DR: In this article , a superconducting magnet with both dipole and quadrupole coils is adopted to generate a dipole field from 0.3 to 3.5 T and a quadruplerupole field with a ramp rate of 0.6 T/s.
Abstract: A compact synchrotron is now under development at the National Institutes for Quantum Science and Technology (QST), with the goal of downsizing the heavy-ion therapy system with superconducting magnets conduction-cooled by GM cryocoolers. The synchrotron is required to accelerate several kinds of heavy-ion beams from 4 MeV/u to 430 MeV/u. A superconducting magnet with both dipole and quadrupole coils is adopted to generate a dipole field from 0.3 to 3.5 T and a quadrupole field from 0.1 to 1.5 T/m with a ramp rate of 0.6 T/s. A coil winding pattern and iron yoke are optimized to achieve field homogeneity in the required area. For the small-scale synchrotron, the coil ends are optimized with a novel parameter combining the beta function and multipole errors considering the beam dynamics.
01 Apr 2022
TL;DR: In this article , the structure and stability of multipole and vortex solitons in the nonlocal nonlinear fractional Schrödinger equation with a gradually decreasing Lévy index, α, are numerically studied.
Abstract: The structure and stability of multipole and vortex solitons in the nonlocal nonlinear fractional Schrödinger equation with a gradually decreasing Lévy index, α, are numerically studied. It is found that the solitons adiabatically compress with the decrease of Lévy index, and new species of stable ones are produced by means of this technique. It is known that, under the action of the normal diffraction (α = 2), the nonlocal cubic self-trapping can support, at most, quadrupole solitons and vortex ones with winding number m = 2 as stable modes in the one- and two-dimensional space, respectively. In contrast to that, we find that the application of the Lévy index management (the gradual decrease of α) leads to the formation of stable five-poles and sextupoles in one-dimensional, and vortices with m = 3 in two-dimensional. Weak dissipation does not essentially affect the observed results.
TL;DR: In this article , the circular intensity difference in second harmonic generation (CID-SHG) was used to investigate the ferroaxial order and its domain states through the transition process of higher-order multipoles such as magnetic-dipole and electric quadrupole.
Abstract: Abstract The spontaneous symmetry breakdown of matter is one of the most important concepts in materials physics and leads to a phase transition into an ordered phase and domain formation in its consequence. The so-called ‘ferroaxial order’ characterized by a rotational structural distortion with an axial vector symmetry has gained growing interest as a new class of ordered state. However, the observation of ferroaxial domain states, that is, clockwise and counterclockwise rotational states, is not straightforward and has been little investigated. Here, we propose that the circular intensity difference in second harmonic generation (CID-SHG) offers an experimental technique to investigate ferroaxial order and its domain states through the transition process of higher-order multipoles such as magnetic-dipole and electric-quadrupole. By using CID-SHG microscopy, we successfully visualize three-dimensional images of ferroaxial domain structures in NiTiO 3 . Our results indicate that CID-SHG is a sensitive probe of ferroaxial order and opens possibilities for the use of ferroaxial materials in nonlinear optical manipulations.
TL;DR: In this article , the authors presented the first accurate and precise dual-mass measurement of individual particles using quadrupole-based ICP-MS, with the assistance of oxygen collision gas.
TL;DR: The T-hetero-nuclear multiple quantum coherence (T-HMQC) sequence using the TRAPDOR (transfer of population in double resonance) recoupling has been introduced for the indirect detection via protons of quadrupolar nuclei with spin I = 1 (14N) or 3/2 (35Cl) in solids at fast magic-angle spinning (MAS) as discussed by the authors .
Abstract: Recently, the T-hetero-nuclear multiple quantum coherence (T-HMQC) sequence using the TRAPDOR (transfer of population in double resonance) recoupling has been introduced for the indirect detection via protons of quadrupolar nuclei with spin I = 1 (14N) or 3/2 (35Cl) in solids at fast magic-angle spinning (MAS). The sequence is simple as it only uses four rectangular pulses and exhibits low t1-noise because the recoupling pulses are applied to the indirectly detected isotope, I. We demonstrate that this sequence is applicable for the detection via protons of spin-1/2 nuclei subject to large chemical shift anisotropy, such as 195Pt. We also report the proton detection of double-quantum (2Q) coherences of 14N nuclei using this sequence. This 2Q version is more robust to the adjustment of the magic angle and the instabilities of the MAS frequencies than its parent single-quantum (1Q) version since the 2Q coherences are not broadened by the first-order quadrupole interaction. In practice, than its 1Q counterpart for the indirect detection of 14N nuclei, the 2Q variant benefits from a slightly higher resolution and comparable sensitivity. In this article, we derive for the first time the Hamiltonian that describes the spin dynamics during the TRAPDOR recoupling. This Hamiltonian demonstrates the importance of the adiabaticity parameter as well as the role of third-order terms in the effective Hamiltonian. The effects of offsets, radio-frequency field, and recoupling time on the efficiency of the T-HMQC sequence are analyzed numerically as well as with experimental detection via protons of 195Pt nuclei in a mixture of cis- and trans-platin and that of 14N and 35Cl isotopes in l-histidine HCl.
TL;DR: In this article , the authors reported 121Sb NQR measurements on kagome superconductor CsV3Sb5 with T c = 2.5 K.
Abstract: We report 121Sb nuclear quadrupole resonance (NQR) measurements on kagome superconductor CsV3Sb5 with T c = 2.5 K. 121Sb NQR spectra split after a charge density wave (CDW) transition at 94 K, which demonstrates a commensurate CDW state. The coexistence of the high temperature phase and the CDW phase between 91 K and 94 K manifests that it is a first order phase transition. The CDW order exhibits tri-hexagonal deformation with a lateral shift between the adjacent kagome layers, which is consistent with 2 × 2 × 2 superlattice modulation. The superconducting state coexists with CDW order and shows a conventional s-wave behavior in the bulk state.
TL;DR: In this paper , a tree-level model in perturbation theory was proposed to estimate the covariance matrix of the halo bispectrum in redshift-space in terms of its multipoles, monopole, quadrupole and hexadecapole.
Abstract: We present the analysis of the halo bispectrum in redshift-space in terms of its multipoles, monopole, quadrupole and hexadecapole, measured from a large set of simulations. We fit such measurements with a tree-level model in perturbation theory that depends on linear and nonlinear bias parameters as well as on the growth rate f of density fluctuations. The likelihood analysis takes advantage of a very large set of mock catalogs, enabling a robust estimation of the covariance properties for all multipoles. We compare the numerical estimate of the covariance matrix to its Gaussian prediction finding discrepancies of 10% or less for all configurations with the sole exception of the squeezed triangles in the monopole case. We find the range of validity of the tree-level model, for the total simulation volume of about 1000 h -3Gpc3, reaches a maximum wavenumber of 0.08 h Mpc-1 for the monopole, while it is limited to 0.06 and 0.045 h Mpc-1 respectively for quadrupole and hexadecapole. Despite this, the addition of the quadrupole to the analysis allows for significant improvements on the determination of the model parameters and specifically on f, similarly to the power spectrum case. Finally, we compare our numerical estimate for the full covariance with its theoretical prediction in the Gaussian approximation and find the latter to work remarkably well in the context of simulation boxes with periodic boundary condition.
TL;DR: In this paper , a three-step periodic drive protocol was proposed to engineer two-dimensional (2D) Floquet quadrupole superconductors and three-dimensional Floquet octupole supercondors hosting zero-dimensional Majorana corner modes (MCMs).
Abstract: We propose a three-step periodic drive protocol to engineer two-dimensional (2D) Floquet quadrupole superconductors and three-dimensional (3D) Floquet octupole superconductors hosting zero-dimensional Majorana corner modes (MCMs), based on unconventional $d$-wave superconductivity. Remarkably, the driven system conceives four phases with only zero MCMs, no MCMs, only anomalous $\ensuremath{\pi}$ MCMs, and both regular zero and anomalous $\ensuremath{\pi}$ MCMs. To circumvent the subtle issue of characterizing zero and $\ensuremath{\pi}$ MCMs separately, we employ the periodized evolution operator to architect the dynamical invariants, namely quadrupole and octupole motion in 2D and 3D, respectively, that can distinguish different higher-order topological phases unambiguously. Our study paves the way for the realization of dynamical quadrupolar and octupolar topological superconductors.
TL;DR: In this article , the double-band inversion of the topology of transition-metal monolayers with two mirror reflections (M x and M y ) has been investigated.
Abstract: Abstract Higher-order topological insulators have been introduced in the precursory Benalcazar-Bernevig-Hughes quadrupole model, but no electronic compound has been proposed to be a quadrupole topological insulator (QTI) yet. In this work, we predict that Ta 2 M 3 Te 5 ( M = Pd, Ni) monolayers can be 2D QTIs with second-order topology due to the double-band inversion. A time-reversal-invariant system with two mirror reflections (M x and M y ) can be classified by Stiefel-Whitney numbers ( w 1 , w 2 ) due to the combined symmetry T C 2 z . Using the Wilson loop method, we compute w 1 = 0 and w 2 = 1 for Ta 2 Ni 3 Te 5 , indicating a QTI with q x y = e /2. Thus, gapped edge states and localized corner states are obtained. By analyzing atomic band representations, we demonstrate that its unconventional nature with an essential band representation at an empty site, i.e., A g @ 4 e , is due to the remarkable double-band inversion on Y–Γ. Then, we construct an eight-band quadrupole model with M x and M y successfully for electronic materials. These transition-metal compounds of A 2 M 1,3 X 5 ( A = Ta, Nb; M = Pd, Ni; X = Se, Te) family provide a good platform for realizing the QTI and exploring the interplay between topology and interactions.
TL;DR: The applicability of the exact multipole decomposition based on spherical harmonics expansion has not been demonstrated around the lattice resonance with the strong multipole coupling as mentioned in this paper , but it has been shown that only a small number of multipoles are required to represent the results accurately.
Abstract: Periodic nanoparticle arrays have attracted considerable interest recently since the lattice effect can lead to spectrally narrow resonances and tune the resonance position in a broad range. Multipole decomposition is widely used to analyze the role of the multipoles in the resonance excitations, radiation, and scattering of electromagnetic waves. However, previous studies have not addressed the validity and accuracy of the multipole decomposition around the lattice resonance. The applicability of the exact multipole decomposition based on spherical harmonics expansion has not been demonstrated around the lattice resonance with the strong multipole coupling. This work studies the two-dimensional periodic arrays of both plasmonic and dielectric nanospheres and compares the multipole decomposition results with the analytic ones around their lattice resonances. We study both the effective polarizabilities of multipoles and the scattering spectra of the structures. The analytical results are calculated from the coupled dipole-quadrupole model. This study demonstrates that the exact multipole decomposition agrees well with the numerical simulation around lattice resonances. Only a small number of multipoles are required to represent the results accurately.
TL;DR: In this paper , it is shown that by breaking the symmetries of such mixed-orbital lattices, it is possible to generate synthetic magnetic flux threading the lattice.
Abstract: Abstract The rich physical properties of multiatomic crystals are determined, to a significant extent, by the underlying geometry and connectivity of atomic orbitals. The mixing of orbitals with distinct parity representations, such as s and p orbitals, has been shown to be useful for generating systems that require alternating phase patterns, as with the sign of couplings within a lattice. Here we show that by breaking the symmetries of such mixed-orbital lattices, it is possible to generate synthetic magnetic flux threading the lattice. We use this insight to experimentally demonstrate quadrupole topological insulators in two-dimensional photonic lattices, leveraging both s and p orbital-type modes. We confirm the nontrivial quadrupole topology by observing the presence of protected zero-dimensional states, which are spatially confined to the corners, and by confirming that these states sit at mid-gap. Our approach is also applicable to a broader range of time-reversal-invariant synthetic materials that do not allow for tailored connectivity, and in which synthetic fluxes are essential.
TL;DR: In this article , the general design process of an HFRS multipole module is described, and test results of the prototype is presented, as well as the development process and test result of the test results for the prototype are presented.
Abstract: HIAF (High Intensity heavy ion Accelerator Facility) is the new generation heavy ion accelerator under construction in China. The HFRS (FRagment Separator of HIAF) is a fragment separator and also a transfer-line between the Booster Ring and the Spectrometer ring, which has magnetic rigidity up to 25 Tm. HFRS magnet system is composed of 11 superconducting dipoles and 13 sets of triplets. Several multipole magnets (an octupole coil, a quadrupole coil, and a sextupole coil) are nested together to compact the length of the HFRS-line. All of them feature high field gradients (13 T/m, 25 T/m2, 105 T/m3) and large bores (320 mm). To reduce the cold mass and ensure the field quality, the whole multipole magnets are all designed with coil-dominated magnets of CCT (Canted Cosine Theta) and DCT (Discrete Cosine Theta). This paper will introduce the general design process of an HFRS multipole module. The development process and test results of the prototype will be presented.
TL;DR: In this paper , the single-particle behavior and nucleon-nucleon correlations were investigated with the electromagnetic moments of Z=21 isotopes and N=28 isotopes as valence neutrons and protons fill the distinctive 0f7/2 orbit, respectively, located between magic numbers, 20 and 28.
TL;DR: In this article , a detailed theoretical framework and analysis to quantitatively analyze the experimental results of Ti L-edge Resonant Elastic X-ray scattering (REXS) of a polar vortex array formed in a PbTiO3/SrTiO 3 superlattice is presented.
Abstract: Resonant elastic X-ray scattering (REXS) offers a unique tool to investigate solid-state systems providing spatial knowledge from diffraction combined with electronic information through the enhanced absorption process, allowing the probing of magnetic, charge, spin, and orbital degrees of spatial order together with electronic structure. A new promising application of REXS is to elucidate the chiral structure of electrical polarization emergent in a ferroelectric oxide superlattice in which the polarization vectors in the REXS amplitude are implicitly described through an anisotropic tensor corresponding to the quadrupole moment. Here, we present a detailed theoretical framework and analysis to quantitatively analyze the experimental results of Ti L-edge REXS of a polar vortex array formed in a PbTiO3/SrTiO3 superlattice. Based on this theoretical framework, REXS for polar chiral structures can become a useful tool similar to x-ray resonant magnetic scattering (XRMS), enabling a comprehensive study of both electric and magnetic REXS on the chiral structures.
TL;DR: In this paper , Mössbauer spectroscopy and X-ray diffraction were used to determine the precision values of the hyperfine interaction parameters and the crystal structure of FeBO3 single crystals in a wide temperature range.