18 research outputs found
Sustainable Value-Sharing Mechanisms of the Industrial Internet of Things Platforms:A Case Study of Haier’s Service-Oriented Transformation
Ensuring fairness and equity in value distribution is crucial for the sustainability of platform ecosystems. However, existing approaches to distributing benefits among cooperative entities often find it difficult to accurately assess each stakeholder’s contributions. This paper tackles this challenge through a case study of the Haier COSMOPlat IIoT platform. By analyzing its value creation and value distribution processes, the research uncovers how platform enterprises can overcome existing limitations by quantifying and revealing intangible customer relationships alongside financial metrics. This revised value-sharing mechanism encourages a shift from “post-event value-sharing” to “mid-event adjustment”, promoting a fair and equitable profit distribution framework that motivates stakeholders toward sustainable value co-creation
Optical-pump terahertz-probe spectroscopy in high magnetic fields with kHz single-shot detection
We demonstrate optical pump/THz probe (OPTP) spectroscopy with a variable
external magnetic field (0-9 T) in which the time-dependent THz signal is
measured by echelon-based single-shot detection at a 1 kHz repetition rate. The
method reduces data acquisition times by more than an order of magnitude
compared to conventional electro-optic sampling using a scanning delay stage.
The approach illustrates the wide applicability of the single-shot measurement
approach to nonequilibrium systems that are studied through OPTP spectroscopy,
especially in cases where parameters such as magnetic field strength (B) or
other experimental parameters are varied. We demonstrate the capabilities of
our measurement by performing cyclotron resonance experiments in bulk silicon,
where we observe B-field dependent carrier relaxation and distinct relaxation
rates for different carrier types. We use a pair of economical linear array
detectors to measure 500 time points on each shot, offering equivalent
performance to camera-based detection with possibilities for higher repetition
rates
Discovery of enhanced lattice dynamics in a single-layered hybrid perovskite
Layered hybrid perovskites have attracted much attention in recent years due
to their emergent physical properties and exceptional functional performances,
but the coexistence of lattice order and structural disorder severely hinders
our understanding of these materials. One unsolved problem regards how the
lattice dynamics are affected by the dimensional engineering of the inorganic
frameworks and the interaction with the molecular moieties. Here, we address
this question by using a combination of high-resolution spontaneous Raman
scattering, high-field terahertz spectroscopy, and molecular dynamics
simulations. This approach enables us to reveal the structural vibrations and
disorder in and out of equilibrium and provides surprising observables that
differentiate single- and double-layered perovskites. While no distinct
vibrational coherence is observed in double-layer perovskites, we discover that
an off-resonant terahertz pulse can selectively drive a long-lived coherent
phonon mode through a two-photon process in the single-layered system. This
difference highlights the dramatic change in the lattice environment as the
dimension is reduced. The present findings pave the way for the ultrafast
structural engineering of hybrid lattices as well as for developing high-speed
optical modulators based on layered perovskites
Nonlinear coupled magnonics: Terahertz field-driven magnon upconversion
Tailored light excitation and nonlinear control of lattice vibrations have
emerged as powerful strategies to manipulate the properties of quantum
materials out of equilibrium. Generalizing the exploitation of coherent
phonon-phonon interactions to nonlinear couplings among other types of
collective modes would open unprecedented opportunities in the design of novel
dynamic functionalities in solids. For example, the collective excitations of
magnetic order - magnons - can efficiently transfer information via spin
current flow, and their coherent and nonlinear control would provide an
attractive route to achieve faster signal processing for next-generation
information technologies. Here, we discover that intense terahertz (THz) fields
can initiate processes of magnon upconversion via coherent magnon-magnon
interactions - a phenomenon that opens the paradigm of nonlinear coupled
magnonics. By using a suite of advanced spectroscopic tools, including a newly
demonstrated two-dimensional (2D) THz polarimetry technique enabled by
single-shot detection, we unveil the unidirectional nature of coupling between
distinct magnon modes of a canted antiferromagnet. Calculations of spin
dynamics further suggest that this coupling is a universal feature of
antiferromagnets with canted magnetic moments. These results demonstrate a
route to inducing desirable energy transfer pathways between coherent magnons
in solids and pave the way for a new era in the development of magnonic signal
processing devices
Observation of polarization density waves in SrTiO3
The nature of the "failed" ferroelectric transition in SrTiO3 has been a
long-standing puzzle in condensed matter physics. A compelling explanation is
the competition between ferroelectricity and an instability with a mesoscopic
modulation of the polarization. These polarization density waves, which should
become especially strong near the quantum critical point, break local inversion
symmetry and are difficult to probe with conventional x-ray scattering methods.
Here we combine a femtosecond x-ray free electron laser (XFEL) with THz
coherent control methods to probe inversion symmetry breaking at finite momenta
and visualize the instability of the polarization on nanometer lengthscales in
SrTiO3. We find polar-acoustic collective modes that are soft particularly at
the tens of nanometer lengthscale. These precursor collective excitations
provide evidence for the conjectured mesoscopic modulated phase in SrTiO3
Development of a baseline model for MAX/MXene synthesis recipes extraction via pre-trained model with domain knowledge
Due to their unique combination of metallic- and ceramic-like properties, MAX phases have attracted a lot of attentions. By selectively etching A-site atoms, MXenes with unique two-dimensional structures can be potentially generated. Due to their extraordinary properties, MXenes have currently made their way to the forefront of various research areas including electronics, photonics and catalysis. Therefore, the development of novel synthesis strategies for MAX/MXene is a key issue for the further development of MAX/MXene. Distilling insights from scientific literatures could accelerate the exploration of novel synthesis recipes; however, manually extracting scattered information from thousands of journal articles is laborious. In this study, we present an annotated corpus incorporating domain knowledge about MAX/MXene synthesis processes, deriving from experimental sections within 110 papers on MAX/MXene research; and based on that, a baseline model (including named entity recognition (NER) and relation extraction (RE) parts) is proposed for distilling information about MAX/MXene synthesis conditions from literatures using pre-trained natural language processing (NLP) models. We also demonstrate the efficacy of the proposed pipeline owning to the joint effort of domain knowledge (about MAX/MXene) and machine learning; where the entity recognition model possessing optimized setting could detect the entities with F1 score of 0.8452, and for relation extraction model with F1 score of 0.8476. It is hoped that the current work would provide an auxiliary for the future research and development of novel MAX/MXenes. In addition, the developed model could serve as a pre-trained model of MAX/MXenes synthesis routes extraction for future data augment
Lineshape characterization of excitons in monolayer WS2 by two-dimensional electronic spectroscopy.
The optical properties of monolayer transition metal dichalcogenides (TMDCs), an important family of two-dimensional (2D) semiconductors for optoelectronic applications, are dominated by two excitons A (XA) and B (XB) located at K/K's valleys. The lineshape of the excitons is an indicator of the interaction of the excitons with other particles and also largely determines the performance of TMDC-based optoelectronic devices. In this work, we apply 2D electronic spectroscopy (2DES), which enables separation of the intrinsic homogeneous linewidth and the extrinsic inhomogeneous linewidth, to dissect the lineshape of XA in monolayer WS2. With a home-built broadband optical parametric amplifier, the 2D spectra give the exciton linewidth values for extensive ranges of excitation densities and temperatures, reflecting inter-exciton and exciton-phonon interactions. Meanwhile, the time-domain evolution of the lineshape reveals a similar rate of spectral diffusion to that in quantum wells (QWs) based on III-V semiconductors