| 查看: 354 | 回复: 4 | ||
| 【奖励】 本帖被评价2次，作者chl5063增加金币 2 个 | ||
| 当前主题已经存档。 | ||
[资源]
《自然》：测量和控制硅材料中电子“旋转”首次实现
|
||
|
据2007年5月18日www.physorg.com网站报告，来自美国特拉华大学和剑桥纳米技术公司的电气工程师们首次展示了如何测量和控制硅元素中电子的旋转属性。硅是世界上使用最广泛的半导体材料，广泛运用于从计算机到手机等电子设备。这项发现有可能极大地推动旋转电子学新领域的发展。旋转电子学旨在控制类似磁体的电子“旋转”属性，而不是仅仅控制电子的电荷，其目的是创造出运算速度更快、更强大的电子设备，比如量子计算机。 美国特拉华大学电气和计算机工程学助理教授伊恩·阿贝尔鲍姆和博士研究生黄弼勤与美国马萨诸塞州剑桥纳米技术公司的创始人之一多维·蒙斯马合作，在特拉华大学伊恩·阿贝尔鲍姆的试验室里进行了此次试验。著名的科学杂志《自然》在其5月17日出版的刊物上对此次试验进行了报告。《自然》杂志还在“新闻和评论”版面上刊登了纽约州立大学物理系的伊格尔·佐迪克特和德国雷根思堡大学理论物理学院的贾罗斯拉维·法比亚恩对特拉华大学团队的研究成果所做的评论，该评论强调称：“现代计算机向传统的以硅元素为基础的电子设备提出了严峻的挑战，对处理器的运算速度、内存存储量和电力消耗等性能的需求空前增加，这迫使研究人员在追求更高性能的过程中对不熟悉的领域进行探索。在这些努力中，阿贝尔鲍姆及其同事汇报了一项可能具有决定性意义的发展成果：他们首次对硅元素中电子旋转的传送和连贯操纵进行了展示。” 操纵电子电荷是当前电子工业的基础，学院派和工业界的科研人员在过去的十年中一直在探索电子旋转承载、处理和储存信息的能力。旋转电子学的主要目标是研究控制电子旋转的精确级别，因为现代电子设备正是通过电子旋转来控制电子电荷的。“电子具有被称为‘旋转’的内禀角动量，”阿贝尔鲍姆强调称：”制造电子旋转设备和电路的第一步是：与反方向的旋转相比，应向半导体中注入更多的某一方向的旋转。” 硅已经成为电子工业中使用极为频繁的材料，它是计算机芯片和晶体管中的电流输送者。硅还有望成为一种高级的旋转电子半导体，我们可以将其称为“旋转传送器”，以前科学家对此并不了解，但现在的试验已经表明硅有能力承载和传导电子的旋转。为了提供硅具有“旋转传送”能力的确实证据，阿贝尔鲍姆和黄弼勤利用为硅片焊接定制的超高真空舱制造出小型硅半导体设备。 旋转注入完成后，硅元素中的电子被置于一个磁场中，该磁场使得电子的旋转方向“产生进动”或不停地转动（非常象旋转陀螺仪的旋转效应），从而在测量过程中产生指示器振动。阿贝尔鲍姆说：“进动和移相的过程，或衰减的过程，是旋转传送最明确的特点。我们的工作首次表明硅元素中可以产生这种效应。这解决了一个最重要的问题，因为硅是电子设备最重要的半导体材料。然而，在其它半导体材料中进行旋转探测时所用过的有效方法未能成功用于硅材料。” 阿贝尔鲍姆说，从事这项研究是一项有风险的工作，但它值得去做。他高度赞扬了数年前蒙斯马向他引荐热电子旋转转送研究并利用热电子旋转转送来解决硅旋转探测问题的举措，那时他和蒙斯马同为哈佛大学的博士后研究员。 当阿贝尔鲍姆还是美国莱塞拉尔理工学院的一名大学生时，他的理想是成为一名内科医生。但是该学院的斯蒂芬·内特尔教授让他改学物理和电气工程，而现在阿贝尔鲍姆像内特尔一样成为了一名大学老师并在特拉华大学教书育人。虽然阿贝尔鲍姆那时决定放弃医学博士的理想，但他现在却有可能被人称之为“旋转电子学”博士。阿贝尔鲍姆说：“我们希望我们的‘旋转电子学’能象1948年贝尔试验室的半导体电子学一样成功。”1948年，贝尔宣布发明了晶体管，这为现代电子学打下了基础。 英文原文链接参见：http://www.physorg.com/news98731293.html |
回复此楼» 猜你喜欢
谈谈两天一夜的“延安行”
已经有6人回复
-
博士申请都是内定的吗？
已经有12人回复
-
氨基封端PDMS和HDI反应快速固化
已经有11人回复
-
之前让一硕士生水了7个发明专利，现在这7个获批发明专利的维护费可从哪儿支出哈？
已经有11人回复
-
论文投稿求助
已经有4人回复
-
Applied Surface Science 这个期刊。有哪位虫友投过的能把word模板发给我参考一下嘛
已经有3人回复
-
投稿精细化工
已经有6人回复
» 本主题相关商家推荐: (我也要在这里推广)
2楼2007-05-25 00:48:24
3楼2007-05-25 08:40:52
4楼2007-05-25 13:30:50
★★★★★ 五星级,优秀推荐
|
Researchers Put 'Spin' in Silicon, Advance New Age of Electronics The world's first silicon spin-transport devices, fabricated and measured in Ian Appelbaum's lab at the University of Delaware. More than 25 individual silicon spin-transport devices are represented, one within each tiny wire grid, on this ceramic chip holder. Credit: Jon Cox, University of Delaware Electrical engineers from the University of Delaware and Cambridge NanoTech have demonstrated for the first time how the spin properties of electrons in silicon--the world's most dominant semiconductor, used in electronics ranging from computers to cell phones--can be measured and controlled. Sponsored Links (Ads by Google) Electronics Design - Analogue-digital-firmware and more; audio-medical-industrial-scientific www.rgctechnical.co.uk Physics - Research all of the articles on NYTimes.com's Knowledge Network www.nytimes.com/college Semiconductor Equipment - Find top quality new, used & refurbished semiconductor equipment www.specequipment.com The discovery could dramatically advance the nascent field of spintronics, which focuses on harnessing the magnet-like "spin" property of electrons instead of solely their charge to create exponentially faster, more powerful electronics such as quantum computers. The experiment, conducted in the laboratory of Ian Appelbaum, assistant professor of electrical and computer engineering at UD, with doctoral student Biqin Huang, and in collaboration with Douwe Monsma, co-founder of Cambridge NanoTech in Cambridge, Mass., is reported in the May 17 issue of the prestigious scientific journal Nature. In commenting on the UD team's research findings in the "News and Views" section, which also was published in the Nature edition, Igor Zutic of the Department of Physics at the State University of New York at Buffalo, and Jaroslav Fabian, of the Institute of Theoretical Physics at the University of Regensburg in Germany, note, "Modern computers present serious challenges for conventional, silicon-based electronics. Ever-increasing demands on processor speed, memory storage and power consumption--the era of the laptop that can keep us warm in winter is fast upon us--are forcing researchers to explore unfamiliar territory in the quest for increased performance. In these endeavours, Appelbaum and colleagues report a possibly decisive development: the first demonstration of the transport and coherent manipulation of electron spin in silicon." While manipulating electron charge is the basis of the present-day electronics industry, researchers in academia and industry over the past decade have been exploring the capability of electron spin to carry, process and store information. A major goal in spintronics is to reach the precise level of control over electron spin that modern electronics has executed over electron charge. "An electron has intrinsic angular momentum called spin," Appelbaum noted. "The first step to making spintronic devices and circuits is to inject more spins of one direction than in the opposite direction into a semiconductor." Silicon has been the workhorse material of the electronics industry, the transporter of electrical current in computer chips and transistors. Silicon also has been predicted to be a superior semiconductor for spintronics, yet demonstrating its ability to conduct the spin of electrons, referred to as "spin transport," has eluded scientists--until now. To provide conclusive evidence of spin transport in silicon, Appelbaum and Huang fabricated small, silicon semiconductor devices using a custom-built, ultra-high vacuum chamber for silicon-wafer bonding. After spin injection, electrons in the silicon were then subjected to a magnetic field, which caused their spin direction to "precess" or gyrate (much like gravity's effect on a rotating gyroscope), producing tell-tale oscillations in their measurement. "The processes of precession and dephasing, or decay, are the most unambiguous hallmarks for spin transport. Our work is the first time anyone has shown this effect in silicon," Appelbaum said. "It's an important problem to solve because silicon is the most important semiconductor for electronics," Appelbaum noted. "However, methods that worked for spin detection in other semiconductors failed in silicon." Appelbaum said that pursuing the research was a risk worth taking. He credits Monsma with introducing him to hot-electron spin transport and applying it to the problem of spin detection in silicon several years ago when they were postdoctoral fellows together at Harvard University. Originally, when Appelbaum entered college as an undergraduate at Rensselaer Polytechnic Institute, he thought he wanted to become a physician. But a professor there, Stephen Nettel, turned him on to physics and electrical engineering, and now Appelbaum is teaching his UD students using Nettel's textbook. So while Appelbaum decided not to become a medical doctor, in some circles he might now be considered, literally, a "spin" doctor. "We hope we're with spintronics where Bell Labs was with semiconductor electronics in 1948," Appelbaum said. That year, Bell announced the invention of the transistor, which laid the foundation for modern electronics. Source: University of Delaware » Next Article in Physics - Physics: Ultra-cold gas makes great magnetometer |
5楼2007-05-26 16:46:09