Probing Strong Electronic Correlations in Ferroelectrics and Multiferroics Through High-Order Harmonic Spectroscopy and First-Principles Calculations

通过高次谐波光谱和第一性原理计算探索铁电体和多铁性中的强电子相关性

• 批准号: 1809181
• 负责人: Michael Chini
• 金额: $ 36.48万
• 依托单位: The University of Central Florida Board of Trustees
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1809181&HistoricalAwards=false
• 关键词: Probing; Strong; Electronic; Correlations; Ferroelectrics

Nontechnical Abstract: One of the goals of modern condensed matter physics is to control the properties of materials so that they can be modified 'on demand'. In relevant materials intense pulses of laser light can force the materials far from equilibrium, dramatically changing their electronic, magnetic, and optical properties. This work focuses on experimental and computational studies of the non-equilibrium properties of such materials which exhibit unique electronic and magnetic responses to external stimuli, induced by intense infrared laser fields. Using advanced laser techniques, the dynamics of interactions in such materials are reconstructed from measurements of light emitted through a process known as high-order harmonic generation. While most previous studies of ultrafast dynamics in solids are performed at the femtosecond and longer timescales (1 femtosecond = 0.000000000000001 seconds), this project seeks to uncover details of the sub-femtosecond dynamics and to establish the link between ultrafast interactions in non-equilibrium materials and the spectral- and time-domain structure of high-order harmonic emission. The experimental and theoretical tools developed through this project can also be used to describe processes relevant to technological applications such as solar energy and spintronics. Students trained as a result of the award will gain experience in advanced laser and computational techniques, as well as state-of-the-art materials synthesis, preparing them for high-tech careers.Technical Abstract: Understanding and controlling the quantum many-body dynamics of strongly-driven, strongly-correlated materials is one of the grand challenges of modern science. Although the nonequilibrium dynamics of strongly-correlated materials have been studied for decades, the few- to sub-femtosecond dynamics of strong electronic correlation have been hidden from experiments. Through measurements and first-principles calculations of the high-order harmonics generated from intense mid-infrared laser fields in bulk and thin-film solids, this project aims to resolve electronic correlations in ferroelectric barium titanate and multiferroic bismuth ferrite crystals, and the role of these correlations in the strong-field laser response. Through measurements of the spectrum, polarization, and time-domain structure of the emitted high-order harmonic radiation, the project reveals the impacts of crystal structure and ferroelectric polarization, Berry curvature, and correlated electron dynamics on the high-order harmonic generation process. Calculations, using time-dependent density functional theory with exchange-correlation functions obtained via dynamical mean-field theory, accurately capture the time-domain Coulomb interactions at the heart of strong electronic correlations. The experimental and theoretical tools developed through this project can also be used to describe processes relevant to technological applications such as solar energy and spintronics. Students trained as a result of the award will gain experience in advanced laser and computational techniques, as well as state-of-the-art materials synthesis, preparing them for high-tech careers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术摘要：现代凝聚态物理学的目标之一是控制材料的特性，以便可以“按需”修改它们。在相关材料中，强烈的激光脉冲可以迫使材料远离平衡状态，从而极大地改变它们的电子、磁性和光学特性。这项工作的重点是此类材料的非平衡特性的实验和计算研究，这些材料对强红外激光场引起的外部刺激表现出独特的电子和磁响应。使用先进的激光技术，通过测量通过称为高阶谐波产生的过程发射的光来重建此类材料中相互作用的动力学。虽然之前大多数固体超快动力学研究都是在飞秒和更长的时间尺度（1飞秒 = 0.000000000000001秒）进行的，但该项目旨在揭示亚飞秒动力学的细节，并建立非平衡材料中的超快相互作用与高次谐波发射的谱域和时域结构之间的联系。通过该项目开发的实验和理论工具还可用于描述与太阳能和自旋电子学等技术应用相关的过程。通过该奖项接受培训的学生将获得先进激光和计算技术以及最先进的材料合成方面的经验，为他们从事高科技职业做好准备。 技术摘要：理解和控制强驱动、强相关材料的量子多体动力学是现代科学的重大挑战之一。尽管强关联材料的非平衡动力学已经研究了几十年，但强电子关联的几到亚飞秒动力学却一直被实验所掩盖。通过测量和第一性原理计算强中红外激光场在块体和薄膜固体中产生的高阶谐波，该项目旨在解决铁电钛酸钡和多铁性铋铁氧体晶体中的电子相关性，以及这些相关性在强场激光响应中的作用。通过测量发射的高次谐波辐射的光谱、偏振和时域结构，该项目揭示了晶体结构和铁电极化、贝里曲率和相关电子动力学对高次谐波产生过程的影响。使用瞬态密度泛函理论和通过动态平均场理论获得的交换相关函数进行计算，可以准确捕获强电子相关性核心的时域库仑相互作用。通过该项目开发的实验和理论工具还可用于描述与太阳能和自旋电子学等技术应用相关的过程。通过该奖项接受培训的学生将获得先进激光和计算技术以及最先进的材料合成方面的经验，为他们从事高科技职业做好准备。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

All-optical sampling of few-cycle infrared pulses using tunneling in a solid

• DOI: 10.1364/prj.420916
• 发表时间: 2021-06-01
• 期刊: PHOTONICS RESEARCH
• 影响因子: 7.6
• 作者: Liu, Yangyang;Gholam-Mirzaei, Shima;Chini, Michael
• 通讯作者: Chini, Michael

Electron-electron interactions and high-order harmonics in solids

• DOI: 10.1103/physrevb.106.235124
• 发表时间: 2022-12
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Didarul Alam;Naseem Ud Din;M. Chini;V. Turkowski

Electron–electron correlations and structural, spectral and polarization properties of tetragonal BaTiO 3

四方 BaTiO 3 的电子-电子相关性以及结构、光谱和偏振特性

• DOI: 10.1088/1361-648x/abaa81
• 发表时间: 2020
• 期刊: Journal of Physics: Condensed Matter
• 作者: Din, Naseem Ud;Jiang, Tao;Gholam-Mirzaei, Shima;Chini, Michael;Turkowski, Volodymyr
• 通讯作者: Turkowski, Volodymyr