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1.
Psychol Res Behav Manag ; 17: 1867-1880, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38712327

RESUMEN

Purpose: Environmental uncertainty has reached unprecedented levels in recent years. While there is substantial knowledge about the connection between environmental uncertainty and organizational outcomes, limited attention has been devoted to investigating its impact on employees' depression and anxiety symptoms. Grounded in job demands-resources theory, this study aims to explore the relationship between environmental uncertainty and employees' depression and anxiety symptoms, and it further investigates the mediating role of work pressure and the moderating role of union practices. Methods: In September 2022, we undertook a cross-sectional survey study, gathering data from 1081 employees across various enterprises situated in Liaoning, China. Throughout this timeframe, notable global occurrences heightened the awareness of environmental uncertainty. Following the exclusion of participants who did not provide information on the main variables, the final valid sample comprised 940 employees. To test all hypotheses, a series of confirmatory factor analyses and path-analytic procedures were conducted using Mplus 7.0. Results: Our results confirm that environmental uncertainty, as a high job demand, increases employees' work pressure, thereby elevating rates of anxiety and depression; the indirect relationship between environmental uncertainty and employees' anxiety and depression through work pressure is stronger when union practices are lower. Conclusion: Our findings indicate the detrimental impact of environmental uncertainty on employees' mental health, and highlight the roles of work pressure and union practices. In light of this, organizations should take steps to mitigate employees' perceptions of environmental uncertainty and establish mental health programs, in cooperation with union practices, to protect employees' mental well-being.

2.
Phys Rev Lett ; 132(19): 193601, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38804949

RESUMEN

Coherent and dissipative interactions between different quantum systems are essential for the construction of hybrid quantum systems and the investigation of novel quantum phenomena. Here, we propose and analyze a magnon-skyrmion hybrid quantum system, consisting of a micromagnet and nearby magnetic skyrmions. We predict a strong-coupling mechanism between the magnonic mode of the micromagnet and the quantized helicity degree of freedom of the skyrmion. We show that with this hybrid setup it is possible to induce magnon-mediated nonreciprocal interactions and responses between distant skyrmion qubits or between skyrmion qubits and other quantum systems like superconducting qubits. This work provides a quantum platform for the investigation of diverse quantum effects and quantum information processing with magnetic microstructures.

3.
Adv Mater ; 36(1): e2306441, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37712832

RESUMEN

The spontaneous formation and topological transitions of vortex-antivortex pairs have implications for a broad range of emergent phenomena, for example, from superconductivity to quantum computing. Unlike magnets exhibiting collinear spin textures, helimagnets with noncollinear spin textures provide unique opportunities to manipulate topological forms such as (anti)merons and (anti)skyrmions. However, it is challenging to achieve multiple topological states and their interconversion in a single helimagnet due to the topological protection for each state. Here, the on-demand creation of multiple topological states in a helimagnet Fe0.5 Co0.5 Ge, including a spontaneous vortex pair of meron with topological charge N = -1/2 and antimeron with N = 1/2, and a vortex-antivortex bundle, that is, a bimeron (meron pair) with N = -1 is reported. The mutual transformation between skyrmions and bimerons with respect to the competitive effects of magnetic field and magnetic shape anisotropy is demonstrated. It is shown that electric currents drive the individual bimerons to form their connecting assembly and then into a skyrmion lattice. These findings signify the feasibility of designing topological states and offer new insights into the manipulation of noncollinear spin textures for potential applications in various fields.

4.
Nano Lett ; 23(24): 11793-11801, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38055779

RESUMEN

The chiral nature of active matter plays an important role in the dynamics of active matter interacting with chiral structures. Skyrmions are chiral objects, and their interactions with chiral nanostructures can lead to intriguing phenomena. Here, we explore the random-walk dynamics of a thermally activated chiral skyrmion interacting with a chiral flower-like obstacle in a ferromagnetic layer, which could create topology-dependent outcomes. It is a spontaneous mesoscopic order-from-disorder phenomenon driven by the thermal fluctuations and topological nature of skyrmions that exists only in ferromagnetic and ferrimagnetic systems. The interactions between the skyrmions and chiral flowers at finite temperatures can be utilized to control the skyrmion position and distribution without applying any external driving force or temperature gradient. The phenomenon that thermally activated skyrmions are dynamically coupled to chiral flowers may provide a new way to design topological sorting devices.

5.
Phys Rev Lett ; 130(10): 106701, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36962022

RESUMEN

We propose a skyrmion-based universal quantum computer. Skyrmions have the helicity degree of freedom in frustrated magnets, where twofold degenerated Bloch-type skyrmions are energetically favored by the magnetic dipole-dipole interaction. We construct a qubit based on them. A skyrmion must become a quantum-mechanical object when its size is of the order of nanometers. It is shown that the universal quantum computation is possible based on nanoscale skyrmions in a magnetic bilayer system. The one-qubit quantum gates are materialized by controlling the electric field and the spin current. The two-qubit gate is materialized with the use of the Ising-type exchange coupling. The merit of the present mechanism is that external magnetic field is not necessary. Our results may open a possible way toward universal quantum computation based on nanoscale topological spin textures.

6.
Ind Health ; 61(2): 112-124, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35444090

RESUMEN

Since the turn of the millennium, the information technology (IT) industry has been growing rapidly in mainland China. One of the significant characteristics of IT employees in mainland China during the past decades was that they tended to work more overtime, which might result in more work-family conflicts and higher turnover rates. Our study tested the mechanism of work-family conflict and work withdrawal behaviors using data from 389 IT employees in mainland China. Using the job demands-resources model and the conservation of resources theory, we examined the mediating effect of emotional exhaustion and the moderating effect of job autonomy. The results indicated that work-to-family conflict was negatively related with work withdrawal behaviors, whereas family-to-work conflict was positively related with work withdrawal behaviors. Moreover, we found the opposite moderating role of job autonomy, which enhanced the relationships between emotional exhaustion and work withdrawal behaviors. That is, the relationship was stronger among employees with higher job autonomy than among those with lower job autonomy. These findings indicate that work-family conflict relates to employees' psychological well-being and behavior, and that job autonomy might play a special role between work-family conflict and work withdrawal behaviors.


Asunto(s)
Conflicto Familiar , Tecnología de la Información , Humanos , Conflicto Familiar/psicología , Satisfacción en el Trabajo , Emociones , China
7.
Stress Health ; 39(3): 539-552, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36251927

RESUMEN

Since the COVID-19 pandemic outbreak, long-term overlooked motives concerning a sense of safety have become a primary concern. People's sense of safety largely depends on the information they receive. Indeed, a tsunami of information about the virus has been disseminated by all forms of media to people's electronic devices, thus permeating their lives. This study proposed that the over-abundance of information, known as information overload, could endanger individuals' sense of safety by increasing their rumination about COVID-19. However, it could also enhance their sense of safety by increasing their positive attitudes toward COVID-19 precautions. Furthermore, we proposed that individuals' hypervigilance could strengthen the relationship between information overload and rumination about COVID-19 and attitudes toward COVID-19 precautions. We tested these hypotheses using a cross-sectional survey study (N = 403) in February 2021 and a diary study (N = 98) in July 2021 in China. The results of both studies support the dual mediating paths of the relationship between information overload and sense of safety. We also found that hypervigilance moderated the relationship between information overload and rumination about COVID-19. Overall, our study offers insights into how social media may influence people's sense of safety and how individual differences in hypervigilance play a role in the process.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Estudios Transversales , Pandemias , Ansiedad
8.
Artículo en Inglés | MEDLINE | ID: mdl-36554690

RESUMEN

In times of uncertainty, such as during COVID-19, many organizations experience profit decline, and employees develop a fear of external threats, such as organizational layoffs. However, most of the literature focuses on how people's fear influences their well-being. Less is known about how employees' fear of external threats influences their workplace behaviors. The current study proposes that supervisors' fear of external threats stimulates those who are high in trait anger to behave in a more abusive way. Simultaneously, subordinates' fear of external threats would strengthen the positive relationship between abusive supervision and their burnout and compulsory citizenship behaviors (CCB), as fear of external threats constrains their response options to abusive supervision. We tested the hypotheses with a multiwave and multisource survey study (N = 322 dyads) in China, and the results showed that supervisors' fear of external threats strengthened the positive effect of trait anger on abusive supervision. Subordinates' fear of external threats strengthens the positive relationships of abusive supervision with CCB and the mediating effect of abusive supervision in the relationship of supervisors' trait anger with subordinates' CCB. Our study enriches people's understanding of how supervisors' and subordinates' fear of external threats may play roles in workplace behaviors.


Asunto(s)
Agotamiento Profesional , COVID-19 , Humanos , Ciudadanía , Miedo , Ira
9.
Nano Lett ; 22(21): 8559-8566, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36259745

RESUMEN

Skyrmions and bimerons are versatile topological spin textures that can be used as information bits for both classical and quantum computing. The transformation between isolated skyrmions and bimerons is an essential operation for computing architecture based on multiple different topological bits. Here we report the creation of isolated skyrmions and their subsequent transformation to bimerons by harnessing the electric current-induced Oersted field and temperature-induced perpendicular magnetic anisotropy variation. The transformation between skyrmions and bimerons is reversible, which is controlled by the current amplitude and scanning direction. Both skyrmions and bimerons can be created in the same system through the skyrmion-bimeron transformation and magnetization switching. Deformed skyrmion bubbles and chiral labyrinth domains are found as nontrivial intermediate transition states. Our results may provide a unique way for building advanced information-processing devices using different types of topological spin textures in the same system.

10.
Phys Rev Lett ; 128(13): 137201, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426702

RESUMEN

The antiferromagnet is considered to be a promising hosting material for the next generation of magnetic storage due to its high stability and stray-field-free property. Understanding the switching properties of the antiferromagnetic (AFM) domain state is critical for developing AFM spintronics. By utilizing the magneto-optical birefringence effect, we experimentally demonstrate the switching rate of the AFM domain can be enhanced by more than 2 orders of magnitude through applying an alternating square-wave field on a single crystalline Fe/CoO bilayer. The observed extraordinary speed can be much faster than that triggered by a constant field with the same amplitude. The effect can be understood as the efficient suppression of the pinning of AFM domain walls by the strong exchange torque triggered by the reversal of the Fe magnetization, as revealed by spin dynamics simulations. Our finding opens up new opportunities to design the antiferromagnet-based spintronic devices utilizing the ferromagnet-antiferromagnet heterostructure.

11.
Adv Mater ; 34(11): e2107908, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34969153

RESUMEN

Magnetic skyrmions are topological swirling spin configurations that hold promise for building future magnetic memories and logic circuits. Skyrmionic devices typically rely on the electrical manipulation of a single skyrmion, but controllably manipulating a group of skyrmions can lead to more compact and memory-efficient devices. Here, an electric-field-driven cascading transition of skyrmion clusters in a nanostructured ferromagnetic/ferroelectric multiferroic heterostructure is reported, which allows a continuous multilevel transition of the number of skyrmions in a one-by-one manner. Most notably, the transition is non-volatile and reversible, which is crucial for multi-bit memory applications. Combined experiments and theoretical simulations reveal that the switching of skyrmion clusters is induced by the strain-mediated modification of both the interfacial Dzyaloshinskii-Moriya interaction and effective uniaxial anisotropy. The results not only open up a new direction for constructing low-power-consuming, non-volatile, and multi-bit skyrmionic devices, but also offer valuable insights into the fundamental physics underlying the voltage manipulation of skyrmion clusters.

12.
Mater Horiz ; 8(3): 854-868, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34821318

RESUMEN

Improvements in computing performance have significantly slowed down over the past few years owing to the intrinsic limitations of computing hardware. However, the demand for data computing has increased exponentially. To solve this problem, tremendous attention has been focused on the continuous scaling of Moore's law as well as the advanced non-von Neumann computing architecture. A rich variety of unconventional computing paradigms has been devised with the rapid development of nanoscale devices. Magnetic skyrmions, spin swirling quasiparticles, have been endowed with great expectations for unconventional computing due to their potential as the smallest information carriers by exploiting their physics and dynamics. In this paper, we provide an overview of the recent progress of skyrmion-based unconventional computing from a joint device-application perspective. This paper aims to build up a panoramic picture, analyze the remaining challenges, and most importantly to shed light on the outlook of skyrmion based unconventional computing for interdisciplinary researchers.

13.
J Phys Condens Matter ; 33(40)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34229301

RESUMEN

Magnetic skyrmions are potential building blocks for future information storage and computing devices. Here, we computationally study the skyrmion dynamics in a cross structure made of two ferromagnetic nanotracks. We show that by controlling the skyrmion motion in the cross structure using spin currents, it is possible to realize the transcription of skyrmion at the intersection of the cross structure at certain conditions. Based on the transcription of skyrmion, we computationally demonstrate the AND, OR and NOT logical gates using the cross structures with modified geometries and appropriate magnetic parameters. Our results may provide guidelines to design future three-dimensional spintronics devices based on magnetic skyrmions.

14.
Nano Lett ; 21(10): 4320-4326, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-33950694

RESUMEN

Magnetic skyrmions are versatile topological excitations that can be used as nonvolatile information carriers. The confinement of skyrmions in channels is fundamental for any application based on the accumulation and transport of skyrmions. Here, we report a method that allows effective position control of skyrmions in designed channels by engineered energy barriers and wells, which is realized in a magnetic multilayer film by harnessing the boundaries of patterns with modified magnetic properties. We experimentally and computationally demonstrate that skyrmions can be attracted or repelled by the boundaries of areas with modified perpendicular magnetic anisotropy and Dzyaloshinskii-Moriya interaction. By fabricating square and stripe patterns with modified magnetic properties, we show the possibility of building reliable channels for confinement, accumulation, and transport of skyrmions, which effectively protect skyrmions from being destroyed at the device edges. Our results are useful for the design of spintronic applications using either static or dynamic skyrmions.

15.
Artículo en Inglés | MEDLINE | ID: mdl-33255704

RESUMEN

Research on positive psychology intervention is in its infancy; only a few empirical studies have proved the effectiveness and benefits of psychological capital interventions in workplaces. From a practical perspective, a more convenient intervention approach is needed for when organizations have difficulties in finding qualified trainers. This study aims to extend the psychological capital intervention (PCI) model and examine its influence on work-related attitudes. A daily online self-learning approach and a randomized controlled trial design are utilized. A final sample of 104 full-time employees, recruited online, is randomly divided into three groups to fill in self-report questionnaires immediately before (T1), immediately after (T2), and one week after (T3) the intervention. The results indicate that the intervention is effective at improving psychological capital (PsyCap), increasing job satisfaction, and reducing turnover intention. The practical implications for human resource managers conducting a flexible and low-cost PsyCap intervention in organizations are discussed. Limitations related to sample characteristics, short duration effect, small sample size, and small effect size are also emphasized. Due to these non-negligible drawbacks of the study design, this study should only be considered as a pilot study of daily online self-learning PsyCap intervention research.


Asunto(s)
Actitud , Intervención basada en la Internet , Satisfacción en el Trabajo , Intervención Psicosocial , Lugar de Trabajo , Humanos , Intervención basada en la Internet/estadística & datos numéricos , Reorganización del Personal/estadística & datos numéricos , Proyectos Piloto , Intervención Psicosocial/métodos , Intervención Psicosocial/estadística & datos numéricos , Encuestas y Cuestionarios , Lugar de Trabajo/psicología , Lugar de Trabajo/estadística & datos numéricos
16.
Phys Rev Lett ; 125(2): 027206, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32701308

RESUMEN

Noninteracting particles exhibiting Brownian motion have been observed in many occasions of sciences, such as molecules suspended in liquids, optically trapped microbeads, and spin textures in magnetic materials. In particular, a detailed examination of Brownian motion of spin textures is important for designing thermally stable spintronic devices, which motivates the present study. In this Letter, through using temporally and spatially resolved polar magneto-optic Kerr effect microscopy, we have experimentally observed the thermal fluctuation-induced random walk of a single isolated Néel-type magnetic skyrmion in an interfacially asymmetric Ta/CoFeB/TaO_{x} multilayer. An intriguing topology-dependent Brownian gyromotion behavior of skyrmions has been identified. The onset of Brownian gyromotion of a single skyrmion induced by thermal effects, including a nonlinear temperature-dependent diffusion coefficient and topology-dependent gyromotion are further formulated based on the stochastic Thiele equation. The experimental and numerical demonstration of topology-dependent Brownian gyromotion of skyrmions can be useful for understanding the nonequilibrium magnetization dynamics and implementing spintronic devices.

17.
Nat Commun ; 11(1): 3577, 2020 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-32681004

RESUMEN

Electrical manipulation of skyrmions attracts considerable attention for its rich physics and promising applications. To date, such a manipulation is realized mainly via spin-polarized current based on spin-transfer torque or spin-orbital torque effect. However, this scheme is energy consuming and may produce massive Joule heating. To reduce energy dissipation and risk of heightened temperatures of skyrmion-based devices, an effective solution is to use electric field instead of current as stimulus. Here, we realize an electric-field manipulation of skyrmions in a nanostructured ferromagnetic/ferroelectrical heterostructure at room temperature via an inverse magneto-mechanical effect. Intriguingly, such a manipulation is non-volatile and exhibits a multistate feature. Numerical simulations indicate that the electric-field manipulation of skyrmions originates from strain-mediated modification of effective magnetic anisotropy and Dzyaloshinskii-Moriya interaction. Our results open a direction for constructing low-energy-dissipation, non-volatile, and multistate skyrmion-based spintronic devices.

18.
Nano Lett ; 20(5): 3299-3305, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32282217

RESUMEN

Magnetic skyrmions are vortex-like spin textures with nontrivial spin topology and novel physical properties that show promise as an essential building block for novel spintronic applications. Skyrmions in synthetic antiferromagnets (SAF) have been proposed long-term to have many advantages than those in ferromagnetic materials, which suffer from fundamental limits for size and efficient manipulation. Thus, experimental realization of skyrmions in SAF is intensely pursued. Here we show the observation of zero-field stable magnetic skyrmions at room temperature in SAF [Co/Pd]/Ru/[Co/Pd] multilayers with Lorentz transmission electron microscope, where uncompensated moments of the SAF provide a medium for the skyrmion characterization. Isolated skyrmions and high-density skyrmions via magnetic field and electromagnetic coordinated methods have been observed, respectively. These created high-density skyrmions maintain at zero-field even when both the current and magnetic field are removed. The use of skyrmions in SAF would advance the process toward practical nonvolatile memories based on spin topology.

19.
Sci Adv ; 6(6): eaay1876, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32083177

RESUMEN

The direct imaging of current density vector distributions in thin films has remained a daring challenge. Here, we report that an inhomogeneous current distribution can be mapped directly by the trajectories of magnetic half-skyrmions driven by an electrical current in Pt/Co/Ta trilayer, using polar magneto-optical Kerr microscopy. The half-skyrmion carries a topological charge of 0.5 due to the presence of Dzyaloshinskii-Moriya interaction, which leads to the half-skyrmion Hall effect. The Hall angle of half-skyrmions is independent of current density and can be reduced to as small as 4° by tuning the thickness of the Co layer. The Hall angle is so small that the elongation path of half-skyrmion approximately delineates the invisible current flow as demonstrated in both a continuous film and a curved track. Our work provides a practical technique to directly map inhomogeneous current distribution even in complex geometries for both fundamental research and industrial applications.

20.
Phys Rev Lett ; 124(3): 037202, 2020 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-32031830

RESUMEN

A magnetic bimeron is a topologically nontrivial spin texture carrying an integer topological charge, which can be regarded as the counterpart of the skyrmion in easy-plane magnets. The controllable creation and manipulation of bimerons are crucial for practical applications based on topological spin textures. Here, we analytically and numerically study the dynamics of an antiferromagnetic bimeron driven by a spin current. Numerical simulations demonstrate that the spin current can create an isolated bimeron in the antiferromagnetic thin film via the dampinglike spin torque. The spin current can also effectively drive the antiferromagnetic bimeron without a transverse drift. The steady motion of an antiferromagnetic bimeron is analytically derived and is in good agreement with the simulation results. Also, we find that the alternating-current-induced motion of the antiferromagnetic bimeron can be described by the Duffing equation due to the presence of the nonlinear boundary-induced force. The associated chaotic behavior of the bimeron is analyzed in terms of the Lyapunov exponents. Our results demonstrate the inertial dynamics of an antiferromagnetic bimeron, and may provide useful guidelines for building future bimeron-based spintronic devices.

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