The superconductor-insulator transition is an archetypal example of a quantum phase transition that plays a crucial role in physics and statistical mechanics. Belonging to different universality classes, the classical...
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The superconductor-insulator transition is an archetypal example of a quantum phase transition that plays a crucial role in physics and statistical mechanics. Belonging to different universality classes, the classical and quantum percolative transitions usually manifest in different systems and are studied separately. Here, we fabricate thickness-gradient FeyTe1−xSex (FTS) films and observe the existence of these two transitions. Variation in the film thickness, which controls substrate misfit and leads to a modification of Fe concentration, results in a superconducting quantum percolative transition. By exposing FTS films to air, we observe a shift in electrical resistivity behavior and a superconducting classical percolative transition. FTS films subjected to the two treatments exhibit very similar phase diagrams, except for different critical exponents. Remarkably, we identify a two-step superconductor-insulator transition at low temperature, where the appearance of superconductive zero resistivity coincides with a sign change in the temperature derivative of electrical resistivity in the normal state. Our analysis can provide a universal scheme to categorize the superconductor-insulator transition in various copper-oxide and iron-based superconductors.
The strong impact of the strain-induced Dzyaloshinskii-Moriya interaction (SIDMI) on the magnetization dynamics of skyrmions in nanomagnetic structures is demonstrated. The effects of SIDMI are characterized by skyrmi...
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The strong impact of the strain-induced Dzyaloshinskii-Moriya interaction (SIDMI) on the magnetization dynamics of skyrmions in nanomagnetic structures is demonstrated. The effects of SIDMI are characterized by skyrmion equations (SEs) of motion and magnetoelastic (ME) equations. The study is performed on a model system of MgO/CoFe/Pt stacked on a piezoelectric substrate. The results demonstrate a major nonlinear amplification in both the first- and higher-harmonic magnitudes of the skyrmion breathing mode due to SIDMI. Remarkably, this enhancement can trigger a skyrmion collapse, enabling its deletion with ultraweak strain-induced excitations. The SIDMI effect is shown to be much more significant than the conventional ME effect. These findings open different avenues for the efficient manipulation of nanomagnetic structures through strain.
Quasi-one-dimensional (1D) materials provide a unique platform for understanding the importance and influence of extended interactions on the physics of strongly correlated systems due to their relative structural sim...
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Quasi-one-dimensional (1D) materials provide a unique platform for understanding the importance and influence of extended interactions on the physics of strongly correlated systems due to their relative structural simplicity and the existence of powerful theoretical tools well adapted to one spatial dimension. Recently, this was highlighted by anomalous observations in the single-particle spectral function A(q,ω) of 1D cuprate chain compounds, measured by angle-resolved photoemission spectroscopy (ARPES), which were explained by the presence of a long-range attractive interaction. Such an extended interaction should leave its fingerprints on other observables, notably the dynamical spin structure factor S(q,ω), measured by neutron scattering or resonant inelastic x-ray scattering. Starting from a simple Hubbard Hamiltonian in 1D and using time-dependent density matrix renormalization group methods, we show that the presence of long-range attractive coupling, directly through an instantaneous Coulomb interaction V or retarded electron-phonon (el-ph) coupling, can introduce significant spectral weight redistribution in S(q,ω) across a wide range of doping. This underscores the significant impact that extended interactions can have on dynamical correlations among particles, and the importance of properly incorporating this influence in modeling. Our results demonstrate that S(q,ω) can provide a sensitive experimental constraint, which complements ARPES measurements, in identifying key interactions in 1D cuprates, beyond the standard Hubbard model.
MoSi2N4 has outstanding potential for applications in electronics, spintronics, and semiconducting fabrication. This attractive scenario can be attributed to its remarkable electronic properties. In this study, we inv...
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Manganese-substituted magnetite ferrofluids(FFs)Mnx Fe_(1-x)Fe_(2)O_(4)(x=0–0.8)were prepared in this work through a chemical coprecipitation *** controlled growth of FF nanomaterials for antibacterial activities is ...
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Manganese-substituted magnetite ferrofluids(FFs)Mnx Fe_(1-x)Fe_(2)O_(4)(x=0–0.8)were prepared in this work through a chemical coprecipitation *** controlled growth of FF nanomaterials for antibacterial activities is challenging,and therefore,very few reports are available on the *** research focuses on stabilizing aqueous FFs with the tetramethylammonium hydroxide surfactant to achieve high *** characterization reveals nanoparticles of 5–11 nm formed by the chemical reaction and nanocrystalline nature,as evident from structural ***-substituted magnetic FFs are analyzed for their structural,functional,and antibacterial performance according to the Mn-substituent *** studies show a high blue shift for Mn^(2+)-substituted Mnx Fe_(1-x)Fe_(2)O_(4)with the theoretical correlation of optical band gaps with the Mn *** superparamagnetic nature of substituted FFs causes zero coercivity and remanence,which consequently influence the particle size,cation distribution,and spin *** structural and functional performance of the FFs is correlated with the antibacterial activity,finally demonstrating the highest inhibition zone formation for Mnx Fe_(1-x)Fe_(2)O_(4)FFs.
Realization of functional flexible artificial synapse is a significant step toward neuromorphic ***,a flexible artificial synapse based on ferroelectric tunnel junctions(FTJs)is demonstrated,using BiFeO_(3)(BFO)thin f...
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Realization of functional flexible artificial synapse is a significant step toward neuromorphic ***,a flexible artificial synapse based on ferroelectric tunnel junctions(FTJs)is demonstrated,using BiFeO_(3)(BFO)thin film as the functional *** inorganic single crystalline FTJs grown on rigid perovskite substrates at high temperatures are integrated with the flexible plastic substrates,by using the water-soluble Sr_(3)Al_(2)O_(6)(SAO)as the sacrificial layer and the following *** transferred freestanding BFO thin film exhibits excellent ferroelectric ***,the memristive properties and the brain-like synaptic learning performance of the flexible FTJs are *** results show that multilevel resistance states were maintained well of the flexible artificial synapse,together with their stable synaptic learning *** work indicates the promising opportunity of ferroelectric thin film based flexible synapse used in the future neuromorphic computing system.
The impact of film thickness and annealing temperature on the structural, electrical, magnetic, and mechanical properties of cobalt–iron–dysprosium (Co40Fe40Dy20 ) thin films deposited on Si(100) substrates have bee...
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We report the experimental demonstration of surface phonon-polaritonic devices in a broad spectral range of 7-13 THz based on SrTiO3. We designed planar ultrafast concentrators that amplifies transient electric field ...
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Hybrid superconductor-semiconductor materials are fueling research in mesoscopic physics and quantum technology. Recently demonstrated smooth β-Sn superconductor shells, due to the increased induced gap, are expandin...
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Hybrid superconductor-semiconductor materials are fueling research in mesoscopic physics and quantum technology. Recently demonstrated smooth β-Sn superconductor shells, due to the increased induced gap, are expanding the available parameter space to new regimes. Fabricated on quasiballistic InSb nanowires, with careful control over the hybrid interface, Sn shells yield measurable switching currents even when nanowire resistance is of order 10kΩ. In this regime Cooper pairs travel through a purely one-dimensional quantum wire for at least part of their trajectory. Here, we focus on the evolution of proximity-induced supercurrent in magnetic field parallel to the nanowire. Long decay up to fields of 1T is observed. At the same time, the decay for higher occupied subbands is notably faster in some devices but not in others. We analyze this using a tight-binding numerical model that includes the Zeeman, orbital, and spin-orbit effects. When the first subband is spin polarized, we observe a dramatic suppression of supercurrent, which is also confirmed by the model and suggests an absence of significant triplet supercurrent generation.
In recent years,there has been a surge of interest in higher-order topological phases(HOTPs)across various disciplines within the field of *** unique phases are characterized by their ability to harbor topological pro...
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In recent years,there has been a surge of interest in higher-order topological phases(HOTPs)across various disciplines within the field of *** unique phases are characterized by their ability to harbor topological protected boundary states at lower-dimensional boundaries,a distinguishing feature that sets them apart from conventional topological phases and is attributed to the higher-order bulk-boundary ***-dimensional(2D)twisted systems offer an optimal platform for investigating HOTPs,owing to their strong controllability and experimental ***,we provide a comprehensive overview of the latest research advancements on HOTPs in 2D twisted multilayer *** will mainly review the HOTPs in electronic,magnonic,acoustic,photonic and mechanical twisted systems,and finally provide a perspective of this topic.
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