Catálogo de publicaciones - revistas

<jats:title>A detailed look into 2D magnetism</jats:title> <jats:p> The van der Waals material chromium triiodide (CrI <jats:sub>3</jats:sub> ) is a ferromagnet in the bulk but appears to become antiferromagnetic when thinned to a few atomic layers. Thiel <jats:italic>et al.</jats:italic> used a local magnetometry technique based on diamond nitrogen-vacancy centers to study the magnetism of these thin films at the nanoscale (see the Perspective by Fernández-Rossier). In agreement with previous results, films with odd numbers of layers had magnetization values consistent with that of a single layer, indicating antiferromagnetic coupling. But when the researchers' probe caused an accidental puncture, the magnetization of a nine-layer film increased approximately ninefold to a value expected in a ferromagnetic material. Further characterization suggested that the puncture had caused a structural transition, linking the structural and magnetic properties of this enigmatic system. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="973" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aav6926">973</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="935" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aax6598">935</jats:related-article> </jats:p>

<jats:title>Decoding the halo pattern</jats:title> <jats:p> Magnetic fields can cause the formation of vortices in a superconductor. In cuprate superconductors, the vortex cores are surrounded by “halos,” where the density of electronic states exhibits a checkerboard pattern. Edkins <jats:italic>et al.</jats:italic> used scanning tunneling spectroscopy to take a closer look into the halos. The results revealed that the patterns correspond to an exotic state called the pair density wave, in which the density of finite momentum Cooper pairs is spatially modulated. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="976" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aat1773">976</jats:related-article> </jats:p>

<jats:title>A radio ridge between two galaxy clusters</jats:title> <jats:p> Galaxy clusters contain dozens or hundreds of galaxies, vast quantities of hot gas, and large amounts of dark matter. The gas can emit at radio wavelengths if it contains electrons at relativistic speeds, which can be injected by active galaxies or accelerated during a merger between two clusters. Govoni <jats:italic>et al.</jats:italic> used the Low-Frequency Array (LOFAR) radio telescope to observe a ridge of radio-emitting plasma extending between two galaxy clusters that are approaching a merger. The results imply that intergalactic magnetic fields connect the two clusters and challenge theories of particle acceleration in the intergalactic medium. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="981" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aat7500">981</jats:related-article> </jats:p>

<jats:title>Something repulsive in the Casimir effect</jats:title> <jats:p> Two uncharged objects (metal plates for instance) will experience an attractive force between them, the magnitude of which increases as they are brought closer together. This force, or Casimir effect, is caused by vacuum fluctuations of the electromagnetic field. Effectively, more modes outside than between the objects results in the objects being pushed together. Zhao <jats:italic>et al.</jats:italic> show that the extent of the electromagnetic fluctuations can be controlled by coating one of the objects with a dielectric (Teflon), which changes the Casimir effect to a repulsive force at small distances. This then cancels out the force between plates and produces a point of stable equilibrium. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="984" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aax0916">984</jats:related-article> </jats:p>

<jats:title>Brain map of touch sensation</jats:title> <jats:p> The brain's somatosensory cortex contains a topographical map that reflects touch sensation inputs. During embryonic development, axons from the midbrain thalamus build columnar connections to the cortex in the absence of sensory input. Working in mice, Antón-Bolaños <jats:italic>et al.</jats:italic> found that these thalamocortical connections are responsible for organizing the somatosensory cortex (see the Perspective by Tiriac and Feller). Organization of the map in the cortex depends on spontaneous calcium waves in the embryonic thalamus. Thus, the somatosensory map is sketched out before actual sensory input begins to refine the details. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="987" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aav7617">987</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="933" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aax8048">933</jats:related-article> </jats:p>

<jats:title>This is safe, you can eat it</jats:title> <jats:p> Social transmission of food preference is a model for studying nonspatial memory. In mice, a signal that food is safe to eat is transmitted by its smell along with molecules in the breath of a conspecific. How the odor itself is encoded and assigned valence is poorly understood. Loureiro <jats:italic>et al.</jats:italic> found a monosynaptic pathway between two brain areas, the piriform cortex and the medial prefrontal cortex, that plays a central role in this process. This connection strengthens during social interaction, thereby allowing a mouse to provide a food safety message to its companion. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6444" page="991" related-article-type="in-this-issue" vol="364" xlink:href="10.1126/science.aaw5842">991</jats:related-article> </jats:p>

<jats:p>A weekly roundup of information on newly offered instrumentation, apparatus, and laboratory materials of potential interest to researchers.</jats:p>