Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 197
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 197
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 271
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3165
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 597
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 511
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 317
Function: require_once
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Currently, theoretical works fail to accurately reproduce the experimental results for the lattice thermal conductivity of boron arsenides (BAs, the natural and isotopically enriched ones). We investigated the microscopic mechanisms of the ultrahigh lattice thermal conductivity () and its unexpected strong temperature-dependence (-dependence) in cubic BAs using the first principles theory within the framework of the Wigner transport theory combined with temperature-dependent interatomic force constants (-IFCs). The contributions of three- and four-phonon scattering processes to the phonon lifetime were included, and temperature-induced phonon renormalization was considered. We found that the of BAs exhibited a strong -dependence ( ∼ ), and -IFCs played important roles in accurately predicting the , especially at high temperatures. We predicted a room-temperature of 1060.51 W m K for BAs, which aligned more closely with the recently measured experimental value of 1000 ± 90 W m K [S. Li , High thermal conductivity in cubic boron arsenide crystals, , , 579-581 (2018)] than previously reported predictions. The superior accuracy of our prediction was attributed to the inclusion of -IFCs in describing phonons and their scattering characteristics. Our results (i) resolved the discrepancy between the theoretically and experimentally obtained , (ii) explained the underlying mechanism of the ultra-high of BAs, and (iii) highlighted the importance of considering the temperature-induced anharmonic renormalization effect at high temperatures. This work provides new insights into accurately predicting the for materials whose phonon dispersions appear harmonic but the are significantly affected by higher-order anharmonic interactions.
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http://dx.doi.org/10.1039/d5cp01538c | DOI Listing |