Catálogo de publicaciones - revistas

<jats:title>Upping the pressure in bilayer graphene</jats:title> <jats:p> The discovery of superconductivity and exotic insulating phases in twisted bilayer graphene has established this material as a model system of strongly correlated electrons. To achieve superconductivity, the two layers of graphene need to be at a very precise angle with respect to each other. Yankowitz <jats:italic>et al.</jats:italic> now show that another experimental knob, hydrostatic pressure, can be used to tune the phase diagram of twisted bilayer graphene (see the Perspective by Feldman). Applying pressure increased the coupling between the layers, which shifted the superconducting transition to higher angles and somewhat higher temperatures. </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="6431" page="1059" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aav1910">1059</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6431" page="1035" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aaw4642">1035</jats:related-article> </jats:p>

<jats:title>Mapping out the magneto-Seebeck coefficient</jats:title> <jats:p> In the Seebeck effect, a temperature difference across a device generates voltage. If the thermal gradient is imposed across a magnetic tunnel junction—with two magnetized layers separated by an insulating tunnel barrier—the magnitude of the generated voltage depends on the relative orientation of the magnetization in the two layers. Transport measurements of this so-called magneto-Seebeck tunneling typically reveal only the signal averaged over the device. Friesen <jats:italic>et al.</jats:italic> created an atomic-scale version of this experiment by using a scanning tunneling microscope with a spin-polarized tip that they scanned across the surface of a magnetic sample. By heating the tip, they were able to map out the spatial dependence of the spin-resolved Seebeck coefficient. </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="6431" page="1065" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aat7234">1065</jats:related-article> </jats:p>

<jats:title>Perovskite quantum emitters</jats:title> <jats:p> The development of many optical quantum technologies is dependent on the availability of solid-state single quantum emitters with near-perfect optical coherence. Light-emitting defects in diamond and quantum dots grown by molecular beam epitaxy have demonstrated transform-limited emission linewidths. However, they are limited in terms of production scalability and reproducibility between individual emitters. Utzat <jats:italic>et al.</jats:italic> now show that perovskite quantum dots can overcome these limitations and provide unprecedented versatility for the generation of indistinguishable single photons or entangled photon pairs for quantum information processing. </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="6431" page="1068" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aau7392">1068</jats:related-article> </jats:p>

<jats:title>Going quantum with radio waves</jats:title> <jats:p> It becomes increasingly difficult to detect long-wavelength single photons because of thermal fluctuations in the background. This can pose problems for single-photon detection for fields such as astronomy and nuclear magnetic resonance imaging. Gely <jats:italic>et al.</jats:italic> used a superconducting qubit, initially developed for circuit quantum electrodynamics (cQED) and quantum information processing for microwaves, to directly observe the quantization of radio-frequency electromagnetic fields stored in a photonic microresonator. They were then able to manipulate the quantum state of the radio-frequency field, forming one- and two-photon Fock states within the microresonator, and analyze how the system interacts dynamically with its environment. The cQED approach could be used for fundamental studies in quantum thermodynamics and also find practical application in imaging. </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="6431" page="1072" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aaw3101">1072</jats:related-article> </jats:p>