Identifying efficient pathways to control and modify the order parameter of a macroscopic phase in materials is an important ongoing challenge. One way to do this is via the excitation of a ...high-frequency mode that couples to the order, and this is the ultimate goal of the field of ultrafast phase transitions1,2. This is an especially interesting research direction in magnetism, where the coupling between spin and lattice excitations is required for magnetization reversal3,4. However, previous attempts5,6 have not demonstrated switching between magnetic states via resonant pumping of phonon modes. Here we show how an ultrafast resonant excitation of the longitudinal optical phonon modes in magnetic garnet films switches magnetization into a peculiar quadrupolar magnetic domain pattern, revealing the magneto-elastic mechanism of the switching. In contrast, the excitation of strongly absorbing transverse phonon modes results in a thermal demagnetization effect only.Resonant excitation of phonons by a laser pulse switches the magnetization of a thin yttrium iron garnet film. This particular combination of longitudinal optical phonons results in a quadrupolar pattern, but this could be tailored in the future.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
We report the first measurement of the charm-mixing parameter yCP in D0 decays to the CP-odd final state ... The study uses the full Belle e+e− annihilation data sample of 976 fb−1 taken at or near ...the ϒð4SÞ centre-of-mass energy. We find ..., where the first uncertainty is statistical, the second is systematic due to event selection and background, and the last is due to possible presence of CP-even decays in the data sample. (ProQuest: ... denotes formula omitted.)
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Gaia Data Release 3 Creevey, O. L.; Sordo, R.; Pailler, F. ...
Astronomy and astrophysics (Berlin),
06/2023, Volume:
674
Journal Article
Peer reviewed
Open access
Gaia
Data Release 3 contains a wealth of new data products for the community. Astrophysical parameters are a major component of this release, and were produced by the Astrophysical parameters ...inference system (Apsis) within the
Gaia
Data Processing and Analysis Consortium (DPAC). The aim of this paper is to describe the overall content of the astrophysical parameters in
Gaia
DR3 and how they were produced. In Apsis, we use the mean BP/RP and mean RVS spectra along with astrometry and photometry, and we derive the following parameters: source classification and probabilities for 1.6 billion objects; interstellar medium characterisation and distances for up to 470 million sources, including a 2D total Galactic extinction map; 6 million redshifts of quasar candidates; 1.4 million redshifts of galaxy candidates; and an analysis of 50 million outlier sources through an unsupervised classification. The astrophysical parameters also include many stellar spectroscopic and evolutionary parameters for up to 470 million sources. These comprise
T
eff
, log
g
, and M/H (470 million using BP/RP, 6 million using RVS), radius (470 million), mass (140 million), age (120 million), chemical abundances (up to 5 million), diffuse interstellar band analysis (0.5 million), activity indices (2 million), H
α
equivalent widths (200 million), and further classification of spectral types (220 million) and emission-line stars (50 000). This paper is the first in a series of three papers, and focusses on describing the global content of the parameters in
Gaia
DR3. The accompanying Papers II and III focus on the validation and use of the stellar and non-stellar products, respectively. This catalogue is the most extensive homogeneous database of astrophysical parameters to date, and is based uniquely on
Gaia
data. It will only be superseded by
Gaia
Data Release 4, and will therefore remain a key reference over the next four years, providing astrophysical parameters independent of other ground- and space-based data.
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Data for φ→γ(ηπ0) are analysed using the KK loop model and compared with parameters of a0(980) derived from Crystal Barrel data. The ηπ mass spectrum agrees closely and the absolute normalisation ...lies just within errors. However, BES parameters for f0(980) predict a normalisation for φ→γ(π0π0) at least a factor 2 lower than is observed. This discrepancy may be eliminated by including constructive interference between f0(980) and σ. The magnitude required for σ→KK is consistent with data on ππ→KK. A dispersion relation analysis by Büttiker, Descotes-Genon and Moussallam of ππ→KK leads to a similar conclusion. Data on ππ→ηη also require decays of σ to ηη. Four sets of ππ→KK data all require a small but definite f0(1370) signal.
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DOBA, FZAB, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this article, we present a two-port on-wafer scattering parameter measurement method to tackle the issue of crosstalk between probes. The proposed method treats the crosstalk separately during the ...system calibration and the device measurement stages because the crosstalk during these stages is often different due to changes in the measurement conditions after the probes have been calibrated. For example, device under test (DUT) and calibration standards are often situated on different substrates, or the distance between probes during calibration is different from that during DUT measurement. Based on this concept, we develop a new error model in which the crosstalk is treated as a standalone two-port error network in parallel with the two-port calibration standards or DUTs. The two-port crosstalk error generated during probing, <inline-formula> <tex-math notation="LaTeX">E_{{\text {CT}}} </tex-math></inline-formula>, is removed in the system calibration and corrected during the measurement of the DUT by using a dummy pair of open-circuit standards that are fabricated on the same substrate as the DUT. Since the crosstalk is corrected while measuring the DUT, rather than during system calibration, we call this method "calibration on the fly" (COF). The method is demonstrated using measurements of a 10-dB attenuator between 140 and 220 GHz.
We use all available baryon acoustic oscillation distance measurements and Hubble parameter data to constrain the cosmological constant Λ, dynamical dark energy, and spatial curvature in simple ...cosmological models. Here, we find that the consensus spatially flat ΛCDM (Λ cold dark matter) model provides a reasonable fit to the data, but depending on the Hubble constant prior and cosmological model, it can be a little more than 1σ away from the best-fitting model, which can favour mild dark energy dynamics or non-flat spatial hypersurfaces.
This paper aims to propose a quantitative tuning method for active disturbance rejection control (ADRC) that controls the K/(Ts + 1) n -type high-order processes. An asymptote in the Nyquist curve ...has been observed for the first time and its mathematical expression has been deduced. An asymptote condition is provided in order to derive a parameter tuning rule under the sensitivity constraint. Although this proposed tuning rule is originally designed for a certain type of high-order processes, it can be extended to other types processes that can be approximated into the form of K/(Ts + 1) n . Comparisons with different PID control strategies have been conducted for a range of cases to demonstrate the efficiency of the proposed tuning method. Finally, the effectiveness of the proposed tuning rule is experimentally verified on water tank system that exhibits high-order dynamics. Field tests on the superheater steam temperature control of a circulating fluidized bed power plant further demonstrate its potential for applications in complex industrial processes.
Selective laser melting (SLM) additive manufacturing of pure tungsten encounters nearly all intractable difficulties of SLM metals fields due to its intrinsic properties. The key factors, including ...powder characteristics, layer thickness, and laser parameters of SLM high density tungsten are elucidated and discussed in detail. The main parameters were designed from theoretical calculations prior to the SLM process and experimentally optimized. Pure tungsten products with a density of 19.01 g/cm
3
(98.50% theoretical density) were produced using SLM with the optimized processing parameters. A high density microstructure is formed without significant balling or macrocracks. The formation mechanisms for pores and the densification behaviors are systematically elucidated. Electron backscattered diffraction analysis confirms that the columnar grains stretch across several layers and parallel to the maximum temperature gradient, which can ensure good bonding between the layers. The mechanical properties of the SLM-produced tungsten are comparable to that produced by the conventional fabrication methods, with hardness values exceeding 460 HV
0.05
and an ultimate compressive strength of about 1 GPa. This finding offers new potential applications of refractory metals in additive manufacturing.
For parameter identifications of robot systems, most existing works have focused on the estimation veracity, but few works of literature are concerned with the convergence speed. In this paper, we ...developed a robot control/identification scheme to identify the unknown robot kinematic and dynamic parameters with enhanced convergence rate. Superior to the traditional methods, the information of parameter estimation error was properly integrated into the proposed identification algorithm, such that enhanced estimation performance was achieved. Besides, the Newton-Euler (NE) method was used to build the robot dynamic model, where a singular value decomposition-based model reduction method was designed to remedy the potential singularity problems of the NE regressor. Moreover, an interval excitation condition was employed to relax the requirement of persistent excitation condition for the kinematic estimation. By using the Lyapunov synthesis, explicit analysis of the convergence rate of the tracking errors and the estimated parameters were performed. Simulation studies were conducted to show the accurate and fast convergence of the proposed finite-time (FT) identification algorithm based on a 7-DOF arm of Baxter robot.
•Optical fiber sensors have several advantages for marine observation.•Marine gives a new opportunity for optical fiber sensing technology.•Overview about optical fiber sensing technology for marine ...observation.•From basic theory to different parameters monitoring in the ocean.
Optical fiber sensors have attracted considerable attention for marine environment and marine structural health monitoring, owing to advantages including resistance to electromagnetic interference, durability under extreme temperature and pressures, light weight, high transmission rate, small size and flexibility. In this paper, the optical fiber sensors employed for marine environment and marine structural health monitoring are summarized for the understanding of their basic sensing principles, and their various sensing applications such as physical parameters, chemical parameters and structural health monitoring. This review paper shows the feasibility of using optical fiber sensing technology for marine application and, due to the aforementioned advantages, it is possible to envisage a widespread use in this research field in the next few years.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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