Boron arsenide thermal record – the second in a week
- Author:Ella Cai
- Release on:2018-07-11
Close on the heels of a US heat-sinking record using the synthetic material boron arsenide, comes a second thermal record using the same material, this time from scientists at University of California, Los Angeles.
The material is being mooted as a high-performance heat-spreader – drawing heat away from hot spots in high-power electronics and photonics.
The UCLA version, which is claimed to be free of thermal-resistance-inducing defects, has achieved an isotropic thermal conductivity of 1,300W/m.K – leaving silicon far behind and is triple that of silicon carbide or copper, although well below diamond – however, diamond is much harder to make.
With their ultra-fast optical spectroscope for thermal measurement, from the left, ther research team of: Professor Yongjie Hu, Huuduy Nguyen, Man Li, Joonsang Kang and Huan Wu
In creating the material, something about the physics of thermal transport through phonons – quantum mechanical modes of lattice vibrations – has been revealed.
“For many decades, theorists consider that three-phonon process governs thermal transport, and the effects of four-phonon and higher-order processes were believed to be negligible, which actually is the true case for most common materials,” said UCLA. “This study makes significant impact to the theory field by showing that high-order anharmonicity through four-phonon process makes important contribution in defect-free boron arsenide single crystals.”
UCLA-boron-arsenide-graphsExperimental measurement, compared with ab initio calculations from independent research groups, support the new theory, according to the
University, which added that the study probed the ballistic thermal transport physics and revealed that long phonon mean free paths explain the origin high thermal conductivity of BAs.
“This achievement and celebration should go to the whole field,” said UCLA researcher Yongjie Hu. “There are many other research groups making progress towards this target. In particular, this success exemplifies the power of combining experiments and ab initio theory in new materials discovery, and I believe this approach will continue to push the scientific frontiers in new materials discovery for many areas including energy, electronics, and photonics applications.”
The material is being mooted as a high-performance heat-spreader – drawing heat away from hot spots in high-power electronics and photonics.
The UCLA version, which is claimed to be free of thermal-resistance-inducing defects, has achieved an isotropic thermal conductivity of 1,300W/m.K – leaving silicon far behind and is triple that of silicon carbide or copper, although well below diamond – however, diamond is much harder to make.
With their ultra-fast optical spectroscope for thermal measurement, from the left, ther research team of: Professor Yongjie Hu, Huuduy Nguyen, Man Li, Joonsang Kang and Huan Wu
In creating the material, something about the physics of thermal transport through phonons – quantum mechanical modes of lattice vibrations – has been revealed.
“For many decades, theorists consider that three-phonon process governs thermal transport, and the effects of four-phonon and higher-order processes were believed to be negligible, which actually is the true case for most common materials,” said UCLA. “This study makes significant impact to the theory field by showing that high-order anharmonicity through four-phonon process makes important contribution in defect-free boron arsenide single crystals.”
UCLA-boron-arsenide-graphsExperimental measurement, compared with ab initio calculations from independent research groups, support the new theory, according to the
University, which added that the study probed the ballistic thermal transport physics and revealed that long phonon mean free paths explain the origin high thermal conductivity of BAs.
“This achievement and celebration should go to the whole field,” said UCLA researcher Yongjie Hu. “There are many other research groups making progress towards this target. In particular, this success exemplifies the power of combining experiments and ab initio theory in new materials discovery, and I believe this approach will continue to push the scientific frontiers in new materials discovery for many areas including energy, electronics, and photonics applications.”
