The discovery of interfacial ferromagnetism in 2D antiferromagnet heterostructures

Nanowerk  December 27, 2022 Combining two different magnetic orders and investigating the magnetic proximity at the interface remains largely unexplored. An international team of researchers (Japan, USA – Purdue University, research org, Pennsylvania State University, Denmark, China) studied the heterostructures of layered antiferromagnets, CrI3 and CrCl3 to characterize the magnetic behaviors down to a few atomic layers. They observed an emergent interfacial ferromagnetism when bringing these two antiferromagnets together, with an even higher critical temperature than both the constituent materials. They demonstrated that an out-of-plane magnetic order was established in the CrCl3 layer proximal to CrI3. The interfacial magnetism showed […]

Researchers show a new way to induce useful defects using invisible material properties

Nanowerk  December 23, 2022 Researchers at the University of Illinois constructed a Dirac material consisting of a chain of magnetic-mechanical resonators and demonstrated that when any of these “atoms” was mechanically excited the excitation spread to the rest of the crystal, just like electrons injected into a semiconductor. After demonstrating that a completely uniform Dirac metamaterial does not allow mechanical excitations to pass through, they introduced a specific set of nonlinearities into the system. This new property added sensitivity to the level of the mechanical excitation and could subtly change the resonance energy of the magneto-mechanical atoms. With the right […]

Designing self-assembling ‘smart materials’

Science Daily  December 12, 2022 The role of hydrodynamic interactions (HIs) play in the self-organization of colloidal suspensions and biological solutions has remained elusive particularly for charged soft matter systems. Researchers in Japan studied the role of HIs in the self-assembly of oppositely charged colloidal particles, which is a promising candidate for electrical tunable soft materials. In many-body HIs and the coupling between the colloid, ion, and fluid motions they found that, under a constant electric field, oppositely charged colloidal particles formed clusters and percolated into a gel network. They revealed that the cluster-forming tendency originates from the incompressibility-induced “inverse […]

Electrons zip along quantum highways in new material

Nanowerk  November 9, 2022 An international team of researchers (USA – University of Chicago, Pennsylvania State University, Israel) discovered a new material, MnBi6Te10, which could be used to create quantum highways useful in connecting the internal components of energy-efficient quantum computers. In the ferromagnetic phase, an energy gap of 15 meV was resolved at the Dirac point on the MnBi2Te4 termination. In contrast, antiferromagnetic MnBi6Te10 exhibited gapless topological surface states on all terminations. Measurements revealed substantial Mn vacancies and Mn migration in ferromagnetic MnBi6Te10. They provided a conceptual framework where a cooperative interplay of these defects drove a delicate change […]

Next generation material that adapts to its history

Nanowerk  November 15, 2022 The responses of living systems dynamically adapt based on the repetition, intensity, and history of stimuli. Such plasticity is ubiquitous in biology, which is profoundly linked to memory and learning. Inspired by living systems, researchers in Finland synthesised micrometre-sized magnetic beads which were then stimulated by a magnetic field. When the magnet was on, the beads stacked up to form pillars. The strength of the magnetic field affects the shape of the pillars, which in turn affects how well they conduct electricity. When they exposed the beads to a quickly pulsing magnetic field, the material became […]

Novel nanowire fabrication technique paves way for next generation spintronics

Nanowerk  November 9, 2022 Eliminating the etching process by directly fabricating nanowires onto the silicon substrate would lead to a marked improvement in the fabrication of spintronic devices. However, when directly fabricated nanowires are subjected to annealing, they tend to transform into droplets as a result of the internal stresses in the wire. Researchers in Japan have developed a new fabrication process to make L10-ordered CoPt nanowires on silicon/silicon dioxide (Si/SiO2) substrates. They coated a Si/SiO2 substrate with a material called a ‘resist’ and subjected it to electron beam lithography and evaporation to create a stencil for the nanowires, deposited […]

One-unit-cell thick semiconductors with room-temperature magnetism

Nanowerk  November 15, 2022 Researchers in China have developed a confined-van der Waals epitaxial approach to synthesizing air-stable semiconducting cobalt ferrite nanosheets with thickness down to one unit cell using a facile chemical vapor deposition process. They demonstrated hard magnetic behavior and magnetic domain evolution by means of vibrating sample magnetometry, magnetic force microscopy and magneto-optical Kerr effect measurements, which showed high Curie temperature above 390 K and strong dimensionality effect. According to the researchers their work provides possibilities for numerous novel applications in computing, sensing and information storage…read more. Open Access TECHNICAL ARTICLE 

Researchers develop a material that mimics how the brain stores information

Nanowerk  November 8, 2022 While a precise modulation of magnetism is achieved when voltage is applied, much more uncontrolled is the spontaneous evolution of magneto-ionic systems upon removing the electric stimuli. An international team of researchers (Spain, Italy, Belgium) has demonstrated a voltage-controllable N ion accumulation effect at the outer surface of CoN films adjacent to a liquid electrolyte, which allows for the control of magneto-ionic properties both during and after voltage pulse actuation (i.e., stimulated, and post-stimulated behavior, respectively). This effect, which takes place when the CoN film thickness is below 50 nm and the voltage pulse frequency is […]

Physicists see light waves moving through a metal

Nanowerk  October 27, 2022 With the discovery of nodal-line semimetals, the notion of the Dirac point has been extended to lines and loops in momentum space. However, experimental evidence for the enhanced correlations in nodal-line semimetals is sparse. An international team of researchers (USA -Columbia University, University of Arkansas, Pennsylvania State University, Florida State University, National High Magnetic Field Laboratory, Flatiron Institute, China, the Netherlands, Germany) found prominent correlation effects in a nodal-line semimetal compound, ZrSiSe, through experiments and density functional theory calculations. They observed two fundamental spectroscopic hallmarks of electronic correlations: strong reduction of the free-carrier Drude weight and […]

The next wonder semiconductor

Science Daily  October 25, 2022 Cubic boron arsenide (BAs) is promising for microelectronics thermal management because of its high thermal conductivity. Recently, its potential as an optoelectronic material was explored. However, it remains challenging to measure its photocarrier transport properties because of small sizes of available high-quality crystals. A team of researchers in the US (UC Santa Barbara, University of Houston) used scanning ultrafast electron microscopy (SUEM) to directly visualize the diffusion of photocarriers in BAs single crystals. They observed ambipolar diffusion at low optical fluence with persistent hot carrier dynamics for above 200 ps, which could likely be attributed […]