近日，美国 芝加哥大学 Alexander A. High团队在Nature Photonics上发文，报道了在原子薄单层二硒化钨tungsten diselenide（WSe2）纳米光子界面中的电可控手性。二氧化钛波导直接制作在低无序氮化硼封装的WSe2表面上。在积分之后，从激子态到波导中的光致发光，可以在平衡发射和定向偏置发射之间电切换。工作原理利用了WSe2中激子态掺杂相关的谷极化。此外，纳米光子波导,可以用作扩散激子通量的近场源，其显示从界面手性继承的谷和自旋极化。这种多功能制造方法，使光子学与范德瓦尔斯异质结构的确定性集成成为可能，并可提供对其激子和电荷载流子行为的光学控制。
Electrically controllable chirality in a nanophotonic interface with a two-dimensional semiconductor
二维半导体的纳米光子界面中的电控手性。
图2：界面静电调谐。
图3：谷极化的栅极依赖性。
图4：谷（自旋）极化激子通量的光子泵浦。
该项研究演示了与六方氮化硼hexagonal boron nitride,hBN封装的、电门控WSe2单层连接的光子波导。界面表现出从0%到20%电可调手性-定向耦合效率chiral–directional coupling efficiency，CDCE，并通过近场激发产生谷（自旋）极化激子通量。
除了线性波导，多功能纳米光子制造方法，可以将过渡金属硫化物TMDCs与更复杂的光子结构连接，其中器件几何形状和尺寸仅，受先进光刻技术限制，使光子环调制器和干涉仪，以及光子晶体中的激子-极化激元成为可能。
结合二维材料大面积生长、剥离和组装的最新进展，这将提高异质结构产量和可扩展性，超越目前限制，这项工作，为其与纳米光子电路的确定性、晶圆级集成，建立了一个通用平台。
重要的是，该界面的可调手性（以前在其他手性光学界面中无法获得）依赖于过渡金属硫化物TMDC单层中激子态掺杂相关的谷动力学。多层和扭曲的范德瓦尔斯异质结构，展示了设计的、奇异的谷特性，也可以与这种波导界面相结合，用于额外手性功能，如栅极可逆发射路由，并提供基于二维材料的新光子逻辑和控制方案。
此外，原子薄半导体中，激子扩散的纳米光子驱动，在分布式光子元件和局部激子电路之间建立了一座桥梁。此外，通过手性过渡金属硫化物TMDC–光子界面的近场光泵浦，可用于产生单层中驻留电荷载流子的自旋极化。这种光学制备的自旋极化电子态，对载流子掺杂水平敏感，可以打破界面时间反演对称性，实现集成纳米光子结构中的栅极激活全光非互易性。
文献链接：https://www.nature.com/articles/s41566-022-00971-7
DOI: https://doi.org/10.1038/s41566-022-00971-7
本文译自Nature。
In addition to improvements in chip performance, the shell packaging technology is also a great breakthrough, IR inversion in the development of field-effect transistor, also known as "FlipFET" on the basis of this year introduced the DirectFET, as shown in Figure 6. Its source and gate inversion result can be directly welded in the printed circuit board, the drain at the top of the weld metal in its shell, if necessary, by the radiator or direct contact with the equipment enclosure. DirectFET size equivalent to the traditional SO-8 plastic (plastic with an area of about 4x5 mm2) shell. In such a small device, the first structure of a double-sided cooling. It is a lead frame, no-lead solder joints of the device, it brought about a series of advantages: it's non-resistor chip package (DFPR) is only 0. 1mW, device thickness of only 0. 7mm, resistance and parasitic inductance have dropped significantly. Such characteristics make it especially suitable for the above-mentioned computer of the latest generation of CPU. In the multi-phase circuits, each with only two of 30 security DirectFET can transfer current. Increase its current rate of 400 per delicate security, the working frequency of 1-2 MHz.Secondly, you must be focused on power semiconductor devices in the IC direction: as a result of the development of MOSFET and IGBT, and their matching to provide a trigger signal power integrated circuit PIC (Power IC) have also developed rapidly. At that time, also known as MOS gate drive MGD (MOS Gate Driver) or control integrated circuit CIC (Control IC). With the expansion of the scope of application: such as motor drives, lighting, various power supply and so on, CIC of the cultivars have been rapidly increasing. These CIC in the development process
And gradually from a simple function to trigger the special needs of a wide range of applications development. PIC is the earliest that can be used in high voltage IC, therefore, also known as high-voltage IC (HVIC). However, many applications such as communications, computers, portable power supply and so on, they do not require high voltage, but demand for the special needs of the development of application specific integrated circuit. Because of their combination and application of power semiconductor devices, we have the power to include them in a class of semiconductor devices. So now the power semiconductor devices in the family, there are many integrated circuits. Many of these power devices with integrated circuits inside, some outside while the separation of power devices. Judging from this point, the limits of power and microelectronics has become increasingly blurred. If a large number of computer applications in power modulation device voltage LDO (Low Drop Out) is one example. It does not belong to switch applications.
As a result of a large number of integrated circuits into the power semiconductor devices, which consider the power semiconductor integrated circuits and devices to do the same in the chip or device on the development of the natural line of thought. Done in the same chip, the original is the concept of power integrated circuits, but their power often relatively small. Done in the same package, easy to increase power capacity, a number of passive components is also possible to join, here often called multi-chip module (MCM).
IR last year iPOWIR developed is a typical multi-chip module. It will power devices to control the use of integrated circuits, or in combination with pulse-width modulation (PWM) integrated circuit, according to the needs of power supply design, using BGA packaging technology portfolio in the same device (as shown in Figure 7) . Multi-chip device that greatly simplifies the power supply design staff. Components reduces the number and percentage of the area, there has been a lot of performance improvement. iPOWIR development is considered DC-DC conversion of the future. But, in fact, a wide range of applications in other fields, as long as the requirements of further integration, MCM structure and will there will be more and more. Therefore, it is the power semiconductor devices important direction of development.
In the above presentation, the development of MOSFET has been referred to as 4C industry provides an important foundation. 4C industries which, at present it is the most active direction of the product. We can understand: in the communications, computer, consumer electronics and automotive development, will require many, many close contacts and IC of all types of power semiconductor devices. Each of these aspects can be used to introduce a lot of space. Not detailed here.
Add: Conclusion
To sum up, the power semiconductor devices the past few years, constantly changed a lot. So can no longer look at a fixed vision of the development of power semiconductor devices. For example, not simply thyristor power semiconductor devices and an equal sign painting, or drawing an equal sign and discrete devices. Must not power semiconductor devices and microelectronics artificially separated, it seems only semiconductor microelectronics. These will impede the development of power semiconductor devices, in the long run will hinder the development of microelectronic devices. Development strategy in order to avoid the power semiconductor devices as a simple process only to be completed on the low-tech products. And the preferential policies available only to integrated circuit industry. China has not been very good to the development of modern power semiconductor devices, the lack of modern power semiconductor devices is a comprehensive understanding of the factors I am afraid. Information technology to stimulate industrialization in the wave, it is imperative that different semiconductor devices have a balanced development.
Conclusion
To sum up, the power semiconductor devices the past few years, constantly changed a lot. So can no longer look at a fixed vision of the development of power semiconductor devices. For example, not simply thyristor power semiconductor devices and an equal sign painting, or drawing an equal sign and discrete devices. Must not power semiconductor devices and microelectronics artificially separated, it seems only semiconductor microelectronics. These will impede the development of power semiconductor devices, in the long run will hinder the development of microelectronic devices. Development strategy in order to avoid the power semiconductor devices as a simple process only to be completed on the low-tech products. And the preferential policies available only to integrated circuit industry. China has not been very good to the development of modern power semiconductor devices, the lack of modern power semiconductor devices is a comprehensive understanding of the factors I am afraid. Information technology to stimulate industrialization in the wave, it is imperative that different semiconductor devices have a balanced development.
欢迎分享，转载请注明来源：内存溢出
微信扫一扫
支付宝扫一扫
评论列表（0条）