{"id":238340,"date":"2025-11-25T15:01:47","date_gmt":"2025-11-25T20:01:47","guid":{"rendered":"https:\/\/today.uconn.edu\/?p=238340"},"modified":"2025-11-25T13:47:22","modified_gmt":"2025-11-25T18:47:22","slug":"breakthrough-materials-master-sound-waves","status":"publish","type":"post","link":"https:\/\/today.uconn.edu\/2025\/11\/breakthrough-materials-master-sound-waves\/","title":{"rendered":"Breakthrough Materials Master Sound Waves"},"content":{"rendered":"

The Wave Engineering for\u00a0eXtreme\u00a0and\u00a0Intelligent\u00a0maTErials\u00a0<\/span>(We-Xite)\u00a0lab<\/span><\/a>,\u00a0led\u00a0by\u00a0engineering assistant professor\u00a0Osama R. Bilal, has\u00a0developed a\u00a0reconfigurable\u00a0metamaterial that\u00a0can control\u00a0sound waves \u2013 bending them, dampening them, or\u00a0focusing\u00a0them\u00a0\u2013\u00a0while encoding\u00a0real-time tuning\u00a0with\u00a0almost\u00a0infinite\u00a0possible shapes.<\/span><\/p>\n

Their work is now published<\/a>\u00a0in the journal Proceedings of the National Academy of Sciences (PNAS).<\/span>\u00a0<\/span><\/p>\n

\u201cMetamaterials are artificial materials that can achieve extraordinary properties not easily found in nature,\u201d explains Ph.D. candidate Melanie Keogh \u201822 (ENG), the first author of the study. In this case, the research team wanted to develop a material that could control sound waves, while being adjustable in both frequency and function, with potential applications ranging from medical imaging to soundproofing.<\/span>\u00a0<\/span><\/p>\n

The metamaterial\u00a0is made up of asymmetrical pillars with\u00a0one or more\u00a0concave faces \u2013\u00a0sort of shaped\u00a0like\u00a0an apple core. These pillars are arranged in an 11×11 grid, with motors controlling the orientation of each pillar.\u00a0The motors are finely tuned, allowing the orientation to be controlled in one-degree\u00a0rotation\u00a0increments.<\/span>\u00a0<\/span><\/p>\n

Sound\u00a0waves, when beamed through the material, bounce off the concavities of the pillars.\u00a0And because each pillar can be individually adjusted, there are an almost infinite number of potential paths\u00a0that can be created\u00a0for the sound waves\u00a0to travel through the grid.<\/span>\u00a0<\/span><\/p>\n

This means that the material can be used to intensify the effect of sound waves by beaming them to a single point. Such applications are\u00a0highly useful\u00a0in\u00a0acoustic tweezers,\u00a0medical imaging techniques such as ultrasound, or in targeted therapeutic techniques.<\/span>\u00a0<\/span><\/p>\n

\u201cImagine something like a brain tumor \u2013 something you want to destroy, but at the same time, you\u00a0can\u2019t\u00a0go in there with a scalpel. You\u00a0can\u2019t\u00a0even go in there with very high-intensity sound,\u00a0at the beginning,\u201d explains Bilal. \u201cSo\u00a0you need to have very low-amplitude waves\u00a0that will focus only\u00a0on\u00a0a single point, and after that will disperse.\u00a0In that way you can weaken a tumor, or attack a kidney stone, or\u00a0you can manipulate small particles\u00a0inside the human body that you\u00a0can\u2019t\u00a0really access\u00a0\u2013 but sound waves can.\u201d<\/span>\u00a0<\/span><\/p>\n

Conversely,\u00a0the\u00a0developed\u00a0metamaterial\u00a0can also be used as\u00a0a\u00a0platform for studying fundamental concepts in\u00a0waves\u00a0physics. One example is\u00a0topological insulators,\u00a0or materials that\u00a0can conduct electricity\u00a0along\u00a0their boundaries but not through their\u00a0core\u00a0\u2014\u00a0a concept\u00a0which\u00a0received the\u00a0Nobel\u00a0Prize in Physics a few years ago. The research team used their metamaterials to control sound\u00a0in\u00a0a similar\u00a0way,\u00a0meaning that the sound waves can be directed to travel along the outside of the material without penetrating it.\u00a0<\/span><\/p>\n

https:\/\/today.uconn.edu\/wp-content\/uploads\/2025\/11\/media4.mp4<\/a><\/video><\/div>\n

 <\/p>\n

In another study, the team is\u00a0using metamaterials\u00a0to reduce drag\u00a0forces\u00a0on moving objects, reducing energy and fuel consumption.<\/span>\u00a0<\/span><\/p>\n

\u201cThis is a big deal for our field, because usually you can have\u00a0a handful of\u00a0stable states that you can tune your material to, but this one here gives us more configurations than the number of atoms in the universe,\u201d says Bilal. \u201cThat\u2019s how significant this is for\u00a0our community.\u201d<\/span>\u00a0<\/span><\/p>\n

Keogh explains that the research team got the idea to use gears or motors to turn the individual pillars because they wanted to solve a persistent engineering problem: \u201cTraditionally, metamaterials are fixed, meaning that they can’t change shape after being manufactured.\u201d For a metamaterial that manipulates sound, this would mean that it could only be \u201ctuned\u201d to control a specific frequency range \u2013 not very versatile. A fixed metamaterial may also become completely ineffective if it is damaged, even by regular wear and tear.<\/span>\u00a0<\/span><\/p>\n

In contrast, this metamaterial \u201callows you to reorient it\u00a0or\u00a0\u2018tune\u2019\u00a0it\u00a0without manufacturing the whole material again,\u201d says Keogh.<\/span>\u00a0<\/span><\/p>\n

And because the motors can be electronically controlled, they make it easier to program the material in real time,\u00a0over and over,\u00a0instead of resorting to re-manufacturing.<\/span>\u00a0<\/span><\/p>\n

\u201cOne\u00a0additional\u00a0thing that is unique about this paper is the combinatorial aspect,\u201d\u00a0Keogh\u00a0elaborates,\u00a0demonstrating\u00a0that the effects of the metamaterial can be controlled even further by\u00a0orienting\u00a0pillars in combination with one another. Two, four, or more pillars moving together constitute a \u201csupercell,\u201d\u00a0which offers even more variables\u00a0for engineers to play with.<\/span>\u00a0<\/span><\/p>\n

\u201cWe can play a lot of tricks\u00a0with\u00a0this\u00a0platform,\u201d says Bilal. \u201cSupercells\u00a0combined with asymmetry\u00a0help\u00a0us expand the design space even further.\u00a0This is\u00a0a very versatile\u00a0approach to tuning metamaterials.\u201d<\/span>\u00a0<\/span><\/p>\n

The immense scope of the design space poses challenges \u2014 with so many potential configurations of the\u00a0pillars,\u00a0it would be impossible to manually calculate how each one\u00a0would\u00a0affect<\/span>\u00a0<\/span>sound waves<\/span>. Keogh jokes that if she began the work now, her grandchildren would still be working on the calculations.<\/span>\u00a0<\/span><\/p>\n

Bilal poses the question this way: “If you\u00a0have\u00a0to navigate the number of atoms in the universe, which one do you pick?”<\/span>\u00a0<\/span><\/p>\n

The research team is turning to AI algorithms and heuristics to help understand how the material will propagate sound across various configurations.\u00a0\u201cThe end\u00a0goal<\/span>\u00a0<\/span>will be a\u00a0<\/span>fully autonomous material that has\u00a0both\u00a0the ability and intelligence to optimize its\u00a0performance\u00a0through\u00a0<\/span>machine learning<\/span>,\u201d says Bilal<\/span>.<\/span>\u00a0\u201cThis material platform brings us\u00a0a step\u00a0closer to reach our\u00a0lab\u00a0vision of wave engineering through extreme and\u00a0intelligent\u00a0materials.\u201d<\/span>\u00a0<\/span><\/p>\n

https:\/\/today.uconn.edu\/wp-content\/uploads\/2025\/11\/media5.mp4<\/a><\/video><\/div>\n

A\u00a0Journey\u00a0Years in the Making<\/h3>\n

Keogh and Bilal\u2019s journey of collaboration began when\u00a0Keogh was an undergraduate, when she took Bilal\u2019s course on vibrations. She began\u00a0doing\u00a0research\u00a0in Bilal\u2019s\u00a0\u201cWe-Xite\u201d\u00a0lab,\u00a0coming\u00a0highly recommended\u00a0by\u00a0a\u00a0fellow professor.<\/span>\u00a0<\/span><\/p>\n

Keogh says she was initially interested in going into industry after she graduated. But through the course of her undergraduate research experience, she realized that work in the lab is often \u201cyears ahead\u201d of the solutions being implemented in industry.\u00a0<\/span>\u00a0<\/span><\/p>\n

\u201cI like being on the cutting edge,\u201d she says.<\/span>\u00a0<\/span><\/p>\n

\u201cFor many years now in our lab, we\u2019ve been trying to program materials to have a certain function, but we\u2019ve always been limited by the number of possibilities we can have,\u201d says Bilal.\u00a0\u201cWhen I started this project with Melanie, I told her, there\u00a0is\u00a0a limitation on the\u00a0number of motors we can control. What happened\u00a0was,\u00a0Melanie,\u00a0who is\u00a0so good with electronics … She just sat down in the lab and\u00a0built all the\u00a0circuitry for this platform.\u00a0This is\u00a0a very big\u00a0project \u2013 you need to stack the pillars in\u00a0a very specific, very precise way, and you need to control every single one of them. She did it, in the most wonderful way you could think of.\u201d<\/span>\u00a0<\/span><\/p>\n

\u201cIn my mind, this is what UConn is all about,\u201d\u00a0he adds. \u201cTraining\u00a0young engineers\u00a0to\u00a0grow and\u00a0mature\u00a0into\u00a0professional, world-class scientists\u00a0is one of the most rewarding parts of being a professor.”<\/span>\u00a0<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

UConn researchers design a programmable metamaterial that can morph into more configurations than there are atoms in the universe, in a blink of an eye<\/p>\n","protected":false},"author":175,"featured_media":238342,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_crdt_document":"","wds_primary_category":0,"wds_primary_series":0,"wds_primary_attribution":0,"footnotes":""},"categories":[1866,2460,2459,2256,2076,1875,2235,2227],"tags":[],"magazine-issues":[],"coauthors":[2413],"class_list":["post-238340","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-engr","category-faculty","category-graduate-students","category-innovation","category-research","category-grad-school","category-today-homepage","category-uconn-edu-homepage"],"pp_statuses_selecting_workflow":false,"pp_workflow_action":"current","pp_status_selection":"publish","acf":[],"publishpress_future_action":{"enabled":false,"date":"2026-05-07 04:42:13","action":"change-status","newStatus":"draft","terms":[],"taxonomy":"category","extraData":[]},"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts\/238340","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/users\/175"}],"replies":[{"embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/comments?post=238340"}],"version-history":[{"count":8,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts\/238340\/revisions"}],"predecessor-version":[{"id":238443,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts\/238340\/revisions\/238443"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/media\/238342"}],"wp:attachment":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/media?parent=238340"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/categories?post=238340"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/tags?post=238340"},{"taxonomy":"magazine-issue","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/magazine-issues?post=238340"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/coauthors?post=238340"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}