{"id":19736,"date":"2021-01-26T20:34:09","date_gmt":"2021-01-26T14:49:09","guid":{"rendered":"https:\/\/www.revoscience.com\/en\/?p=19736"},"modified":"2021-01-26T20:37:28","modified_gmt":"2021-01-26T14:52:28","slug":"first-timeelectrons-caught-flowing-like-water","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/first-timeelectrons-caught-flowing-like-water\/","title":{"rendered":"First Time:Electrons Caught Flowing like Water"},"content":{"rendered":"\n

We often speak of electrons \u201cflowing\u201d through materials, but in fact, they do not normally move like a liquid. Such \u201chydrodynamic\u201d electron flow had been predicted, though, and Weizmann Institute of Science researchers recently managed, with the help of a unique technique\u00a0to image electrons flowing like the water flowing in a pipe. This is the first time such \u201cliquid electron flow\u201d has been visualized, and it has vital implications for future electronic devices.<\/p>\n\n\n\n

\"\"
A \u201criver\u201d of electrons flowing in a graphene channel. The viscosity generated by the repulsion between electrons (red balls) causes them to flow with a parabolic current density, illustrated here as a white foam wavefront<\/em><\/figcaption><\/figure>\n\n\n\n

Electrons usually move through conductors more like a gas thana liquid. That is, they do not collide with one another, but rather, they tend to bounce off impurities and imperfections in the material. A fluid flow, in contrast, takes it shape \u2013 be it waves or whirlpools \u2013 from frequent collisions between the particles in liquid.  <\/p>\n\n\n\n

To make electrons flow like a liquid, one needs a different kind of conductor, and the team turned to graphene, which is a one-atom-thick sheet of carbon, and which can be made exceptionally clean. \u201cTheories suggest that liquid electrons can perform cool feats that their non-liquid counterparts cannot. But to get a clear-cut proof that electrons can, indeed, form a liquid state, we wanted to directly visualize their flow,\u201d said Prof. Shahal <\/a>Ilani head of the team in the Institute\u2019s Condensed Matter Physics Department.<\/p>\n\n\n\n

To image the electron flow in the graphene, the researchers needed to develop a technique that would be both powerful enough to peer inside a material, yet gentle enough to avoid disrupting the\u00a0flow. The Weizmann team created such a technique, as they recently reported in\u00a0Nature Nanotechnology<\/em>. This method uses\u00a0a nanoscale detector built from a carbon-nanotube transistor<\/a>, and the team found that can image the properties of flowing electrons with unprecedented sensitivity. \u201cOur technique is at least 1000 times more sensitive than alternate methods; this enables us to image phenomena that previously could only be studied indirectly,\u201d says Dr. Joseph Sulpizio, in Ilani\u2019s lab.<\/p>\n\n\n\n

In a new study published in Nature<\/em>, the Weizmann researchers applied their novel imaging technique to state-of-the-art graphene devices<\/a> produced in the group of Prof. Andre Geim at the University of Manchester. These devices were nanoscale channels designed to guide the flowing electrons. The team observed the hallmark signature of hydrodynamic flow: Just like water in a pipe, the electrons in the graphene flowed faster in the center of the channel and slowed down at the walls.<\/p>\n\n\n\n

This demonstration \u2013 that under the right conditions, electrons can mimic the patterns of a conventional liquid \u2013  may prove beneficial for creating new types of electronic devices, including low-power ones in which hydrodynamic flow lowers the electrical resistance. \u201cComputing centers and consumer electronics are devouring an ever increasing amount of energy, and it\u2019s imperative to find ways to make electrons flow with less resistance,\u201d said Dr. Lior Ella, also of Ilani\u2019s group.<\/p>\n\n\n\n

The experimental group at Weizmann also included Asaf Rozen and Debarghya Dutta. The graphene devices were produced by John Birkbeck, Dr. David Perello, and Dr. Moshe Ben-Shalom from the group of Prof. Andre Geim at the University of Manchester. Theoretical calculations and computer simulations to support the experiments were performed by Dr. Thomas Scaffidi, Dr. Tobias Holder, Dr. Raquel Queiroz, Dr. Alessandro Principi and Prof. Ady Stern.<\/p>\n","protected":false},"excerpt":{"rendered":"

A \u201criver\u201d of electrons flowing in a graphene channel. The viscosity generated by the repulsion between electrons (red balls) causes them to flow with a parabolic current density, illustrated here as a white foam wavefront<\/p>\n","protected":false},"author":2,"featured_media":19737,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[121,17],"tags":[],"class_list":["post-19736","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-physics","category-research"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",927,1200,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press-200x200.jpg",200,200,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press-309x400.jpg",309,400,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press-768x994.jpg",750,971,true],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press-675x874.jpg",675,874,true],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",927,1200,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",927,1200,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",618,800,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",440,570,false],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",600,777,false],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",464,600,false],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press-760x490.jpg",760,490,true],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press-550x360.jpg",550,360,true],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press-95x65.jpg",95,65,true],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",640,828,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",74,96,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/01\/Ilani_electron_river_foam-press.jpg",150,194,false]},"author_info":{"info":["RevoScience"]},"category_info":"Physics<\/a> Research<\/a>","tag_info":"Research","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/19736","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=19736"}],"version-history":[{"count":0,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/19736\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/19737"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=19736"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=19736"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=19736"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}