Bipolar Spintronic Devices with Two-Dimensional Systems

具有二维系统的双极自旋电子器件

• 批准号: 1810266
• 负责人: Igor Zutic
• 金额: $ 31.78万
• 依托单位: SUNY at Buffalo
• 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: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1810266&HistoricalAwards=false
• 关键词: Bipolar; Spintronic; Devices; Two; Dimensional

Semiconductor devices in which the recombination of carriers (electrons and oppositely charged holes) leads to the emission of light (photons) play an increasingly important role. Advances in light emitting diodes (LEDs), recognized by the 2014 Nobel Prize in Physics, demonstrate many advantages over conventional light bulbs, including lower power consumption, longer lifetime, smaller size, and reduced environmental concerns. While in LEDs and lasers the focus is on the emission wavelength and intensity, their utility can be significantly enhanced by also harnessing the polarization of the emitted light. Akin to a preferred hand use in humans (left vs right), the polarization of light can display handedness (left vs right or clockwise vs counterclockwise). This preference is also inherent to many otherwise identical molecules and can signal different biological functions. The polarization-sensitive detection can be used for biomedical diagnosis, including an early detection of cancer. The proposed research investigates polarization control in light emitting diodes and lasers to improve their detection sensitivity as well as enable a much faster operation and lower power consumption. The principle behind this polarization control is the conservation of the total angular momentum when it is converted between different subsystems, such as carriers and photons. In a simple mechanical manifestation, the conservation of angular momentum causes the rotational frequency of ice skaters to increase when their arms are pulled closer to their spinning bodies. In light emitting devices the angular momentum of carriers is associated with their spin that is analogous to a child's top spinning in the clockwise or counterclockwise direction. Through transfer of angular momentum of spin-polarized carriers that preferentially spin in one these directions, the emitted light becomes polarized. The proposed work will provide a closely integrated educational and outreach efforts, as well as develop resources to study spintronics, including Spintronics Handbook: Spin Transport and Magnetism, 2nd Edition, co-edited by the PI. To address a deficiency in the secondary education in which a vast majority of public school students have minimal or no exposure to physical sciences that subsequently deters them from considering careers in science or engineering, the PI will organize Summer Workshops: Light Emitting Diodes and Lasers. The topics will include light diffraction, wavelength measurement, polarization properties of lasers, and modification of laser output. As a part of the annual SPIE: Optics+Photonics Conference, the PI will organize Symposia to bridge the gap between the spintronics and optics communities.The success of practical spintronic devices operating at room temperature is largely limited to unipolar devices where spin-polarized electrons are responsible for magnetoresistive effects implemented in spinvalves. Despite their remarkable success for magnetic storage and sensing, such spin valves are of limited use for advanced signal processing and digital logic. It would therefore be important to assess if there are alternative paths to realize potentially transformative spin-based devices, beyond magnetoresistance. Two paths towards superior light emitting devices are sought: (1) using conventional semiconductors and (2) using novel van der Waals materials that can be made atomically thin. In (1) it is predicted that silicon as the dominant material for conventional electronic, but with poor optical properties, could also lead to the robust light emission and thereby provide unexplored opportunities for silicon optoelectronics. In (2) an atomically-thin active region enables reduction in size and the emission of light is achieved at a fraction of the power consumed in conventional counterparts. In contrast to the common approach for spin-based devices that aims to increase the carrier spin relaxation time, it is predicted that short spin relaxation time supports ultrafast changes in the polarization of the emitted light ( 200 GHz at 300 K) and thereby enables ultrafast optical communication. Theoretical predictions will be closely supported through experimental collaborations to ensure their demonstration.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.

载流子(电子和相反电荷的空穴)的复合导致光(光子)发射的半导体器件发挥着越来越重要的作用。2014年诺贝尔物理学奖认可的发光二极管(LED)的进步显示出许多优于传统灯泡的优点，包括更低的功耗、更长的寿命、更小的尺寸和更少的环境问题。虽然LED和激光的重点是发射波长和强度，但也可以通过利用发射光的偏振来显著提高它们的实用性。类似于人类首选的手部使用(左手和右手)，光的偏振可以表现出惯用手(左手和右手或顺时针和逆时针)。这种偏好也是许多其他相同的分子所固有的，可以发出不同的生物功能信号。偏振敏感检测可用于生物医学诊断，包括癌症的早期检测。这项拟议的研究对发光二极管和激光器的偏振控制进行了研究，以提高其检测灵敏度，并实现更快的操作和更低的功率消耗。这种偏振控制背后的原理是，当总角动量在不同的子系统(如载流子和光子)之间转换时，它是守恒的。在一个简单的机械表现形式中，角动量守恒导致滑冰运动员的旋转频率在他们的手臂被拉近他们的旋转身体时增加。在发光设备中，载体的角动量与它们的自转有关，这类似于儿童的陀螺沿顺时针或逆时针方向旋转。通过优先在这些方向上旋转的自旋偏振载流子的角动量转移，发射的光变得偏振。拟议的工作将提供紧密结合的教育和外联工作，并开发研究自旋电子学的资源，包括由国际和平研究所共同编辑的自旋电子学手册：自旋运输和磁性，第二版。为了解决中学教育中的一个不足，即绝大多数公立学校的学生对物理科学的接触很少或根本没有接触，这使他们不敢考虑从事科学或工程职业，PI将组织暑期讲习班：发光二极管和激光。主题包括光衍射、波长测量、激光的偏振特性和激光输出的修改。作为一年一度的SPIE：光学+光子学会议的一部分，PI将组织研讨会，以弥合自旋电子学和光学界之间的差距。实用的自旋电子器件在室温下运行的成功很大程度上仅限于单极器件，在单极器件中，自旋极化的电子负责在SPVALE中实现磁阻效应。尽管它们在磁存储和传感方面取得了显著的成功，但这种自旋阀在高级信号处理和数字逻辑方面的用途有限。因此，重要的是评估是否有替代的途径来实现潜在的变革性的自旋为基础的器件，而不是磁阻。人们寻找了两条通往更好发光器件的途径：(1)使用传统半导体和(2)使用可以原子变薄的新型范德华材料。在(1)中预测，硅作为传统电子学的主导材料，但其光学性能较差，也可能导致强大的发光，从而为硅光电子学提供未知的机会。在(2)中，原子薄的有源区能够减小尺寸，并且光的发射是以传统的有源区消耗的功率的一小部分实现的。与通常的基于自旋的器件旨在增加载流子自旋弛豫时间的方法不同，预测短的自旋驰豫时间支持发射光的偏振的超快变化(在300K时为200 GHz)，从而实现超快光通信。理论预测将通过实验合作得到密切支持，以确保它们得到证实。这一奖项反映了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

Resonant tunneling anisotropic magnetoresistance induced by magnetic proximity

• DOI: 10.1103/physrevb.102.045312
• 发表时间: 2020-04
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Chenghao Shen;T. Leeney;A. Matos-Abiague;B. Scharf;Jong E. Han;I. Žutić

Nanoelectronics with proximitized materials

• DOI: 10.1016/j.sse.2019.03.015
• 发表时间: 2019-05
• 期刊: Solid-State Electronics
• 影响因子: 1.7
• 作者: I. Žutić;A. Matos-Abiague;B. Scharf;T. Zhou;H. Dery;K. Belashchenko

Superconducting Proximity Effect in InAsSb Surface Quantum Wells with In Situ Al Contacts

• DOI: 10.1021/acsaelm.0c00269
• 发表时间: 2020-08-25
• 期刊: ACS APPLIED ELECTRONIC MATERIALS
• 影响因子: 4.7
• 作者: Mayer, William;Schiela, William F.;Shabani, Javad
• 通讯作者: Shabani, Javad

Probing tunneling spin injection into graphene via bias dependence

通过偏置依赖性探测石墨烯中的隧道自旋注入

• DOI: 10.1103/physrevb.98.054412
• 发表时间: 2018
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Zhu, Tiancong;Singh, Simranjeet;Katoch, Jyoti;Wen, Hua;Belashchenko, Kirill;Žutić, Igor;Kawakami, Roland K.
• 通讯作者: Kawakami, Roland K.

Intensity equations for birefringent spin lasers

• DOI: 10.1103/physrevb.103.045306
• 发表时间: 2020-11
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Gaofeng Xu;J. Cao;Velimir Labinac;I. Žutić