LaAlO3中电子和离子拉曼散射产生相干声子的比较

M. Neugebauer, D. M. Juraschek, M. Savoini, P. Engeler, L. Boie, E. Abreu, N. Spaldin, S. Johnson
{"title":"LaAlO3中电子和离子拉曼散射产生相干声子的比较","authors":"M. Neugebauer, D. M. Juraschek, M. Savoini, P. Engeler, L. Boie, E. Abreu, N. Spaldin, S. Johnson","doi":"10.1103/PHYSREVRESEARCH.3.013126","DOIUrl":null,"url":null,"abstract":"In ionic Raman scattering, infrared-active phonons mediate a scattering process that results in the creation or destruction of a Raman-active phonon. This mechanism relies on nonlinear interactions between phonons and has in recent years been associated with a variety of emergent lattice-driven phenomena in complex transition-metal oxides, but the underlying mechanism is often obscured by the presence of multiple coupled order parameters in play. Here, we use time-resolved spectroscopy to compare coherent phonons generated by ionic Raman scattering with those created by more conventional electronic Raman scattering on the nonmagnetic and non-strongly-correlated wide band-gap insulator LaAlO$_3$. We find that the oscillatory amplitude of the low-frequency Raman-active $E_g$ mode exhibits a sharp peak when we tune our pump frequency into resonance with the high-frequency infrared-active $E_u$ mode, consistent with first-principles calculations. Our results suggest that ionic Raman scattering can strongly dominate electronic Raman scattering in wide band-gap insulating materials. We also see evidence of competing scattering channels at fluences above 28~mJ/cm$^2$ that alter the measured amplitude of the coherent phonon response.","PeriodicalId":8467,"journal":{"name":"arXiv: Materials Science","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2020-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"5","resultStr":"{\"title\":\"Comparison of coherent phonon generation by electronic and ionic Raman scattering in \\nLaAlO3\",\"authors\":\"M. Neugebauer, D. M. Juraschek, M. Savoini, P. Engeler, L. Boie, E. Abreu, N. Spaldin, S. Johnson\",\"doi\":\"10.1103/PHYSREVRESEARCH.3.013126\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"In ionic Raman scattering, infrared-active phonons mediate a scattering process that results in the creation or destruction of a Raman-active phonon. This mechanism relies on nonlinear interactions between phonons and has in recent years been associated with a variety of emergent lattice-driven phenomena in complex transition-metal oxides, but the underlying mechanism is often obscured by the presence of multiple coupled order parameters in play. Here, we use time-resolved spectroscopy to compare coherent phonons generated by ionic Raman scattering with those created by more conventional electronic Raman scattering on the nonmagnetic and non-strongly-correlated wide band-gap insulator LaAlO$_3$. We find that the oscillatory amplitude of the low-frequency Raman-active $E_g$ mode exhibits a sharp peak when we tune our pump frequency into resonance with the high-frequency infrared-active $E_u$ mode, consistent with first-principles calculations. Our results suggest that ionic Raman scattering can strongly dominate electronic Raman scattering in wide band-gap insulating materials. We also see evidence of competing scattering channels at fluences above 28~mJ/cm$^2$ that alter the measured amplitude of the coherent phonon response.\",\"PeriodicalId\":8467,\"journal\":{\"name\":\"arXiv: Materials Science\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2020-10-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"5\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv: Materials Science\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1103/PHYSREVRESEARCH.3.013126\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv: Materials Science","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1103/PHYSREVRESEARCH.3.013126","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 5

摘要

在离子拉曼散射中,红外主动声子介导散射过程,导致拉曼主动声子的产生或破坏。这种机制依赖于声子之间的非线性相互作用,近年来与复杂过渡金属氧化物中出现的各种晶格驱动现象有关,但潜在的机制往往被多个耦合顺序参数的存在所掩盖。在这里,我们使用时间分辨光谱来比较离子拉曼散射产生的相干声子与更传统的电子拉曼散射在非磁性和非强相关的宽带隙绝缘体LaAlO$_3$上产生的相干声子。我们发现,当我们将泵浦频率调整为与高频红外主动$E_u$模式共振时,低频拉曼主动$E_g$模式的振荡幅度呈现出一个尖锐的峰值,这与第一性原理计算一致。我们的研究结果表明,离子拉曼散射在宽禁带绝缘材料中可以强烈地支配电子拉曼散射。我们还看到在28~mJ/cm$^2$以上的影响下存在竞争散射通道的证据,这改变了相干声子响应的测量振幅。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Comparison of coherent phonon generation by electronic and ionic Raman scattering in LaAlO3
In ionic Raman scattering, infrared-active phonons mediate a scattering process that results in the creation or destruction of a Raman-active phonon. This mechanism relies on nonlinear interactions between phonons and has in recent years been associated with a variety of emergent lattice-driven phenomena in complex transition-metal oxides, but the underlying mechanism is often obscured by the presence of multiple coupled order parameters in play. Here, we use time-resolved spectroscopy to compare coherent phonons generated by ionic Raman scattering with those created by more conventional electronic Raman scattering on the nonmagnetic and non-strongly-correlated wide band-gap insulator LaAlO$_3$. We find that the oscillatory amplitude of the low-frequency Raman-active $E_g$ mode exhibits a sharp peak when we tune our pump frequency into resonance with the high-frequency infrared-active $E_u$ mode, consistent with first-principles calculations. Our results suggest that ionic Raman scattering can strongly dominate electronic Raman scattering in wide band-gap insulating materials. We also see evidence of competing scattering channels at fluences above 28~mJ/cm$^2$ that alter the measured amplitude of the coherent phonon response.
求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信