In the heat transfer highway, thermal energy travels through quantum particles called phonons. But at the nanoscale in today’s most advanced semiconductors, those phonons don’t remove enough heat. Purdue researchers are therefore focused on opening new nanoscale lanes on the heat transfer highway using hybrid quasiparticles called “polaritons.” Credit: Purdue University Photo/DALL-E
In the heat transfer highway, thermal energy travels through quantum particles called phonons. but,
nanoscale today’s cutting edge
semiconductor, those phonons do not remove enough heat. Purdue researchers are therefore focused on opening new nanoscale lanes on the heat transfer highway using hybrid quasiparticles called “polaritons.”
thomas beachem
really like
heat transfer. He talks about it loudly and proudly, like a preacher in a big tent revival.
“There are several ways to describe energy,” says Beechem, an associate professor of mechanical engineering. “When we talk about light, we describe it in terms of particles called ‘photons.’ Heat also transports energy in a predictable manner. We call these energy waves “phonons.” However, in some materials, photons and phonons can come together to create new objects called “polaritons.” It carries energy in a unique way, different from photons and phonons. ”
Like photons and phonons, polaritons are not physical particles that can be seen or captured. These are similar ways of describing energy exchange.
as if
They were particles.
Still vague? How about another analogy? “Phonons are like an internal combustion engine, and photons are like an electric car,” Beechem says. “Polaritons are Toyota’s Prius. They are a hybrid of light and heat, retaining some of the properties of both. But they are special in their own right.”
Polariton is used in optical applications ranging from stained glass to home health testing. However, their ability to transfer heat has been largely ignored, as the effect becomes noticeable only when the size of the material becomes very small. “We now know that phonons do most of the heat-transferring work,” says Dr. Jacob Minyard. student in Beechem’s lab. “Polariton effects are observable only at the nanoscale. But thanks to semiconductors, we haven’t had to deal with heat transfer at that level until now.”
“Semiconductors have become incredibly small and complex,” he continued. “The people who design and manufacture these chips are starting to realize that phonons do not dissipate heat efficiently at very small scales. Our paper shows that on such length scales polaritons are not very efficient at conducting heat. We have demonstrated that we can contribute to a larger portion of the rate.”
Their research on polaritons was selected as a featured article in a magazine.
applied physics journal
.
DOI: 10.1063/5.0173917
Source: scitechdaily.com
