EFRI NewLAW: Magnetic Field Free Magneto-optics and Chiral Plasmonics with Dirac Materials

EFRI NewLAW：采用狄拉克材料的无磁场磁光和手性等离子体

基本信息

批准号：
1741673
负责人：
Lian Li
金额：
$ 199.88万
依托单位：
West Virginia University Research Corporation
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-01 至 2023-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1741673&HistoricalAwards=false
关键词：
EFRI NewLAW Magnetic Field Free

项目摘要

Most natural phenomena obey "time-reversal symmetry", which states that if the direction of time is reversed, for example, the propagation of light waves is the same in both forward and backward directions. But optical transport that only lets light pass one-way, termed "non-reciprocal propagation", is vital for energy reduction and noise suppression in telecommunications. The generation of non-reciprocity requires breaking time-reversal symmetry, and typically can be realized in magneto-optical materials via the Faraday effect (where light passing through a material is subject to an external magnetic field, thus changing the light wave orientation). This fundamental requirement of an external magnetic field places significant limitations on device miniaturization and on-chip integration. This program researches a new material platform "gapped Dirac materials" whose intrinsic Berry curvature, a key and newly-recognized property of their energy band structure, can act as an effective magnetic field - thus giving rise to unique chiral edge plasmon resonances that can facilitate non-reciprocal light propagation. The outcome of this research will enable compact, magnetic-field-free (and thus lightweight and energy-efficient) tunable nonreciprocal devices for optical communications and quantum information processing. This project will train graduate and under-represented students in STEM in a multidisciplinary environment; provide outreach to the public through programs such as Research Experience for Teachers, "Science on Tap" public lectures, and "Broaden the Horizon" that focuses on middle school female students; and develop and distribute analysis tools and codes under open source licenses.This project explores a new frontier in magneto-optics and magnetic-field-free non-reciprocal light transport based on Dirac materials such as transition-metal dichalcogenide monolayers, where the breaking of inversion symmetry and large spin-orbit coupling lead to valley-spin locking. The intrinsic Berry curvature of these materials further acts as an effective magnetic field in momentum space, which under a valley imbalance can give rise to chiral plasmon modes that enable non-reciprocal light propagation at mid infrared and terahertz frequencies. Valley polarization in these gapped Dirac materials will be induced through three approaches: 1) doping with transition-metal impurities; 2) proximity to layered magnetic transition-metal phosphorous trichalcogenides; and 3) electrical spin injection. Electromagnetic modeling and calculations of the Berry curvature, magneto optical effects, and chiral plasmons in selected monolayers and heterostructures will provide guidance for material synthesis by molecular beam epitaxy and chemical vapor deposition, and atomic scale characterization with spin-resolved scanning tunneling microscopy/spectroscopy, angle-resolved photoemission spectroscopy, and polarization selective photoluminescence, as well as far-field optical characterization and near-field scanning optical microscopy imaging. Through an integrated experimental-theoretical approach, this project aims to demonstrate wave guiding chiral plasmons in the mid-infrared to terahertz range to enable magnetic-field-free optical devices such as non-reciprocal Faraday isolators and tunable optical circulators.

大多数自然现象遵守“时间反转对称性”，该现象指出，例如，如果时间方向逆转，则在向前和向后方向的光波传播相同。但是，只能使光通过单向，称为“非转流传播”的光学传输对于电信中的能量还原和抑制噪声至关重要。非生产力的产生需要打破时间反转的对称性，通常可以通过法拉第效应在磁光材料中实现（其中通过材料的光照受外部磁场的影响，从而改变光波方向）。这种对外部磁场的基本要求对设备微型化和芯片积分施加了重大限制。该程序研究了一个新的材料平台“间隙狄拉克材料”，其内在的浆果曲率是其能量带结构的关键和新认可的特性，可以作为一个有效的磁场 - 从而引起独特的手性等离子等离子体的共振，从而促进非交流光传播。这项研究的结果将实现用于光学通信和量子信息处理的紧凑，无磁场（因此轻巧且能效）的非偏置设备。该项目将在多学科环境中培训STEM的毕业生和代表性不足的学生；通过诸如教师的研究经验，“ Tap in Tap”公开演讲以及“扩大地平线”等计划，向公众提供宣传，该计划重点介绍了中学女学生；并开发和分发分析工具和代码在开源许可下。该项目探索了基于狄拉克材料（例如过渡金属二进制元素化元素单层）的磁极磁和无磁性非磁性非磁性光传输的新领域，在该材料中，反转对称性和大型Spin-Orbit coupling coupllit couplley couplley spinley spin leds leds valley spin loce loce。这些材料的固有浆果曲率进一步充当动量空间中的有效磁场，在山谷不平衡下，这会引起手性等离子体模式，该模式在中期红外和terahertz频率下实现了非逆向光传播。这些间隙的狄拉克材料中的山谷极化将通过三种方法诱导：1）与过渡金属杂质掺杂； 2）靠近分层的磁过渡金属磷酸盐元素； 3）电旋转注射。选定的单层和异质结构中浆果曲率，磁光光学效应和手性等离子体的电磁模型和计算，将通过分子束外延和化学蒸汽沉积和原子量表表征分子束的外延和化学蒸气量表表征，并通过分子束外延和化学蒸汽量表进行指导，以旋转的扫描型倾向显微镜和分解型散发型散发型散发型散布型散布型散布型，并有效。光致发光以及远场光学表征和近场扫描光学显微镜成像。通过综合实验理论方法，该项目旨在证明中红外的波动性手性等离子体到Terahertz范围，以实现无磁场光学设备，例如非重新磁性的Faraday隔离器和可调的光学循环器。