CAREER: Continuous-wave Terahertz laser employing HTS Josephson junctions

职业：采用 HTS 约瑟夫森结的连续波太赫兹激光器

• 批准号: 2045957
• 负责人: Timothy Benseman
• 金额: $ 50万
• 依托单位: CUNY Queens College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-03-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2045957&HistoricalAwards=false
• 关键词: CAREER; Continuous; wave; Terahertz; laser

Proposal Number: 2045957Principal Investigator: Timothy M BensemanTitle: CAREER: Continuous-wave Terahertz laser employing HTS Josephson junctionsInstitution: CUNY Queens CollegeNontechnical AbstractPowerful and lightweight lasers that operate at frequencies between 0.3 trillion Hertz and 1.5 trillion Hertz will offer a leap forward for numerous applications, such as secure and ultrafast wireless data networking, detection of concealed drugs and explosives, and early-warning identification of tooth decay and skin cancer. They will far surpass the capabilities of lasers and laser-like electromagnetic radiation sources currently available in this frequency range, which either have low power output, or are too large, heavy, and power-consuming to be used in field-portable applications. This project establishes a new type of laser technology uniquely based on high-temperature superconductors that will be ideal for the above applications in this ‘terahertz gap’ frequency range. To date, milliwatt-level power from this type of laser has only been theoretically predicted, at the level of fundamental physics. This project tests the ideas empirically and engineers the technology to make it available for deployment. The cryocooling requirements of this technology take advantage of micro-cryocoolers that are already used for infrared cameras and night vision goggles. To complement the superconductivity research project, a program of scientific outreach activities is performed. These are based on superconductive levitation experiments to inspire high schoolers and community college students, particularly from underrepresented demographics, into STEM fields. A graduate-level course module focuses on lithographic fabrication techniques for microelectronics and prepares students for careers in device microfabrication research.Technical AbstractAt present, the sources of coherent radiation available between approximately 0.3 trillion Hertz and 1.5 trillion Hertz all have serious engineering drawbacks that limit their usefulness. Existing technologies that work at these frequencies either generate very low levels of output power, or are very heavy, bulky, and power-consuming. User-friendly lasers operating in this ‘terahertz gap’ range would revolutionize a number of fields, including high-bandwidth data transmission, scientific and medical imaging, and security and defense technologies. Stacked ‘intrinsic’ superconductor-insulator-superconductor (Josephson) junctions in the extremely anisotropic high-temperature superconducting compound Bi2Sr2CaCu2O8 are one of the most promising candidates for filling the ‘terahertz gap’. These intrinsic Josephson junctions can be used to engineer the only compact terahertz laser source that currently offers tunability, high power, and continuous-wave operation. This project engineers terahertz laser sources based on Bi2Sr2CaCu2O8 Josephson junctions to achieve at least an order-of-magnitude enhancement in the terahertz power output of these devices to 1 milliwatt or more, while also at least doubling their operating frequency range to at least 1.0 terahertz. These enhancements in terahertz power and emission frequency are targeted even at operation temperatures of 77 Kelvin or more, in order to minimize cryocooling requirements. Terahertz sources are microfabricated by patterning stacks on Bi2Sr2CaCu2O8 crystals using optical lithography and argon-ion milling. The feasibility of doing this at volume for commercial-scale terahertz laser applications will be tested. Finally, a further research aim of this project is to measure the behavior of a novel type of Josephson plasmon in Bi2Sr2CaCu2O8. Experimentally understanding this plasmon would make it possible to engineer an entire new class of highly efficient electronic devices for terahertz signal detection and mixing.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.

项目编号：2045957首席研究员：Timothy M bensem标题：职业：采用高温高温约瑟夫森结的连续波太赫兹激光器功率强大且重量轻的激光器工作频率在0.3万亿赫兹到1.5万亿赫兹之间，将为许多应用提供飞跃式的发展，如安全和超快的无线数据网络，隐藏毒品和爆炸物的检测，以及蛀牙和皮肤癌的早期预警识别。它们将远远超过目前在该频率范围内可用的激光和类似激光的电磁辐射源的能力，这些电磁辐射源要么功率输出低，要么太大、太重、太耗电，无法用于现场便携式应用。该项目建立了一种基于高温超导体的新型激光技术，这将是在“太赫兹间隙”频率范围内上述应用的理想选择。到目前为止，这种类型的激光的毫瓦级功率只是在基础物理学的水平上进行了理论上的预测。该项目对这些想法进行了经验测试，并设计了技术，使其可用于部署。这项技术的低温冷却要求利用了已经用于红外摄像机和夜视镜的微型低温冷却器。为了补充超导研究项目，执行了一项科学推广活动计划。这些都是基于超导悬浮实验，以激励高中生和社区大学生，特别是来自代表性不足的人口，进入STEM领域。研究生水平的课程模块侧重于微电子的光刻制造技术，并为学生在器件微制造研究方面的职业做好准备。目前，在0.3万亿赫兹到1.5万亿赫兹之间可用的相干辐射源都存在严重的工程缺陷，限制了它们的使用。在这些频率下工作的现有技术要么产生非常低的输出功率，要么非常笨重、笨重、耗电。在这个“太赫兹间隙”范围内工作的用户友好型激光器将彻底改变许多领域，包括高带宽数据传输、科学和医学成像以及安全和国防技术。在极各向异性高温超导化合物Bi2Sr2CaCu2O8中堆叠的“本征”超导体-绝缘体-超导体（Josephson）结是填补“太赫兹间隙”最有希望的候选者之一。这些固有的约瑟夫森结可用于设计目前提供可调谐，高功率和连续波操作的唯一紧凑太赫兹激光源。该项目设计了基于Bi2Sr2CaCu2O8 Josephson结的太赫兹激光源，使这些设备的太赫兹功率输出至少提高了一个数量级，达到1毫瓦或更高，同时将其工作频率范围至少提高了一倍，达到至少1.0太赫兹。即使在77开尔文或更高的工作温度下，这些太赫兹功率和发射频率的增强也是为了最大限度地减少冷冻冷却要求。利用光学光刻和氩离子铣削技术，在Bi2Sr2CaCu2O8晶体上形成图案化堆叠，实现了太赫兹源的微加工。在商业规模的太赫兹激光应用中大量使用这种方法的可行性将被测试。最后，本项目的进一步研究目标是测量Bi2Sr2CaCu2O8中新型约瑟夫森等离子体的行为。通过实验了解这种等离子体将使设计一种全新的用于太赫兹信号检测和混合的高效电子设备成为可能。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。