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1.
二维材料中由贝里曲率诱导的新型磁学响应是近年来的新兴领域.这些二维材料所表现出的磁学特性及量子输运与贝里曲率直接相关,而贝里曲率又与晶体的对称性、电子的轨道磁性、自旋轨道耦合以及磁电效应等息息相关.研究这些新型磁性响应一方面有益于研究不同量子效应间的耦合作用,另一方面可探索量子效应在电子与信息器件领域的应用.本文介绍了近几年来二维材料中新型磁响应的实验研究进展,特别介绍了二硫化钼和石墨烯等材料中的谷霍尔和磁电效应、低对称性的二碲化钨等材料中的量子非线性霍尔以及转角石墨烯中的反常霍尔和量子反常霍尔效应.本文结合二维材料的晶体结构以及电子结构,介绍了这些新奇现象的现有物理解释、回顾了相关研究的最新发展、讨论了其中尚未理解的现象,并作出展望.  相似文献   

2.
超快激光技术是目前激光乃至物理学和信息科学领域最活跃的研究前沿之一,在工业加工、生物医学和激光雷达等领域具有广泛应用。二维材料具有独特的物理结构及优异的光电特性,作为可饱和吸收体应用于超快激光器时,具备工作波段宽、调制深度可控和恢复时间快等优势。其中,过渡金属硫化物因具有带隙连续可调等特点,已成为二维材料研究领域的重点。本文从过渡金属硫化物的特性出发,介绍了可饱和吸收器件的制作方法,综述了基于新型过渡金属硫化物的超快激光器的研究进展,并对其发展趋势进行了展望。  相似文献   

3.
石墨烯以其独特的光电特性打开了二维纳米材料的大门,随后拓扑绝缘体、过渡金属硫化物、黑磷等二维材料相继被报道,这些材料由于具有良好的非线性光学特性,可用作被动饱和吸收体来产生脉冲激光.本文总结了近年来基于二维材料的光纤激光器和固体激光器的研究状况,从激光器的中心波长、脉宽、重复频率、脉冲能量和输出功率等基本参数对发展现状进行了阐述,最后进行了总结和展望.  相似文献   

4.
二维范德瓦尔斯材料(可简称二维材料)已发展成为备受瞩目的材料大家族,而由其衍生的二维范德瓦尔斯异质结构的集成、性能及应用是现今凝聚态物理和材料科学领域的研究热点之一.二维范德瓦尔斯异质结构为探索丰富多彩的物理效应和新奇的物理现象,以及构建新型的自旋电子学器件提供了灵活而广阔的平台.本文从二维材料的转移技术着手,介绍二维范德瓦尔斯异质结构的构筑、性能及应用.首先,依据湿法转移和干法转移的分类,详细介绍二维范德瓦尔斯异质结构的制备技术,内容包括转移技术的通用设备、常用转移方法的具体操作步骤、三维操纵二维材料的方法、异质界面清洁.随后介绍二维范德瓦尔斯异质结构的性能和应用,重点介绍二维磁性范德瓦尔斯异质结构,并列举在二维范德瓦尔斯磁隧道结和摩尔超晶格领域的应用.因此,二维材料转移技术的发展和优化将进一步助力二维范德瓦尔斯异质结构在基础科学研究和实际应用上取得突破性的成果.  相似文献   

5.
二维范德瓦尔斯材料(可简称二维材料)已发展成为备受瞩目的材料大家族,而由其衍生的二维范德瓦尔斯异质结构的集成、性能及应用是现今凝聚态物理和材料科学领域的研究热点之一.二维范德瓦尔斯异质结构为探索丰富多彩的物理效应和新奇的物理现象,以及构建新型的自旋电子学器件提供了灵活而广阔的平台.本文从二维材料的转移技术着手,介绍二维范德瓦尔斯异质结构的构筑、性能及应用.首先,依据湿法转移和干法转移的分类,详细介绍二维范德瓦尔斯异质结构的制备技术,内容包括转移技术的通用设备、常用转移方法的具体操作步骤、三维操纵二维材料的方法、异质界面清洁.随后介绍二维范德瓦尔斯异质结构的性能和应用,重点介绍二维磁性范德瓦尔斯异质结构,并列举在二维范德瓦尔斯磁隧道结和摩尔超晶格领域的应用.因此,二维材料转移技术的发展和优化将进一步助力二维范德瓦尔斯异质结构在基础科学研究和实际应用上取得突破性的成果.  相似文献   

6.
以石墨烯为代表的二维纳米材料可饱和吸收体以其独特的非线性光学特性被广泛应用于超快光纤激光器.本文总结了近年来二维纳米材料作为可饱和吸收体在中红外超快光纤激光器中的研究发展,介绍了二维纳米材料原子结构、非线性光学特性、可饱和吸收体器件集成方式,及其在中红外超快光纤激光器中的应用,重点阐述了基于黑磷可饱和吸收体实现的2μm飞秒光纤激光器,并对二维纳米材料可饱和吸收体在中红外超快光纤激光器中的发展与挑战进行了展望.  相似文献   

7.
首先综述了基于二维光催化剂的电子结构调控方式,包括厚度调节、元素掺杂、缺陷工程和异质结的设计等。其次,由于半导体异质结在减少光生电子空穴复合速度方面具有独特的优势,着重介绍了由二维材料与其它不同维数的半导体界面组成的异质结的研究进展。最后介绍了新型二维光催化材料在析氢、CO_2还原、固氮和污染物降解等方面的应用。总结文献可知,二维材料与块体材料相比,具有较高的比表面积、表面存在大量的活性位点、能更有效地分离催化剂中的载流子、合适的能带结构、可调节的光吸收区等特点。文末总结了目前的研究现状和面临的挑战,并展望了二维材料在光催化中的应用前景。  相似文献   

8.
以石墨烯为代表的二维材料在二维半导体等领域具有重要的应用价值,因此得到了广泛的研究。二维超导体不仅丰富了二维材料的物理内容,而且具有潜在的应用价值,已成为备受关注的超导前沿领域之一。文章回顾了二维超导材料的研究历史,重点介绍了几种具有代表性的(准)二维超导材料及其存在的物理问题,并对二维超导材料的研究进行了展望。  相似文献   

9.
吴春婷  姜妍  戴通宇  张晚秋 《发光学报》2018,39(11):1584-1597
2 μm掺钬固体激光器的输出波长处在大气窗口和人眼安全区,在激光雷达、激光测距、光电对抗和激光医学等方面都有重要应用,因此在2 μm固体激光器研究领域中成为一个研究热点。本文介绍了2 μm掺钬固体激光器能级系统及常用的掺钬晶体,并对基于这些晶体的钬激光器研究进展进行了综述,最后对2 μm钬固体激光器的未来发展方向等进行展望。  相似文献   

10.
本文介绍了高鸿钧课题组在物理所20年来的部分代表性工作.研究的主要方向为低维纳米功能材料的分子束外延可控制备、生长机制、物性调控及其在未来信息技术中的原理性应用.从材料的可控制备入手,结合第一性原理的理论计算,阐明材料生长机制和结构与物性的关系,进而实现物性调控和原理性应用.主要内容有:1)纳米尺度"海马"分形结构的形成及其生长机制;2)STM分辨率的提高及最高分辨Si(111)-7×7原子图像的获得;3)固体表面上功能分子的吸附、组装及其机制;4)稳定、重复、可逆的纳米尺度电导转变与超高密度信息存储;5)固体表面上单分子自旋态的量子调控及其原理性应用;6)原子尺度上朗德g因子的空间分辨及其空间分布不均匀性的发现;7)晶圆尺寸、高质量、单晶石墨烯的制备及原位硅插层绝缘化;8)几种新型二维原子晶体材料的可控构筑及其物性调控;9)"自然图案化"的新型二维原子晶体材料及其功能化.这些工作为低维量子结构的构造、物性调控及其原理性应用奠定了基础.  相似文献   

11.
Ultrafast lasers play an important role in a variety of applications ranging from optical communications to medical diagnostics and industrial materials processing. Graphene and other two-dimensional(2D) noncarbon materials, including topological insulators(TIs), transition metal dichalcogenides(TMDCs), phosphorene, bismuthene, and antimonene, have witnessed a very fast development of both fundamental and practical aspects in ultrafast photonics since 2009. Their unique nonlinear optical properties enable them to be used as excellent saturable absorbers(SAs) that have fast responses and broadband operation, and can be easily integrated into lasers. Here, we catalog and review recent progress in the exploitation of these 2D noncarbon materials in this emerging field. The fabrication techniques, nonlinear optical properties, and device integration strategies of 2D noncarbon materials are first introduced with a comprehensive view. Then, various mode-locked/Q-switched lasers(e.g., fiber, solid-state, disk, and waveguide lasers) based on 2D noncarbon materials are reviewed. In addition, versatile soliton pulses generated from the mode-locked fiber lasers based on 2D noncarbon materials are also summarized. Finally, future challenges and perspectives of 2D materials-based lasers are addressed.  相似文献   

12.
This paper presents a review of the organic solid-state polymer materials, which have become established as a new laser media. The photostability of these materials is discussed. Different types of solid-state lasers built around these materials are also reviewed.  相似文献   

13.
We report the first demonstration of autocatalysis and oscillatory behaviour in the solid-state where no decomposition process is involved. Our material system is solid-state silica glass impregnated with hydrogen. It is at the heart of photosensitivity in glass-based optical waveguides and devices, which have many applications including telecommunication devices, fibre lasers, and optical sensors. Consequently, the results reported here extend the engineering of chemical complexity to a previously uncharted area in materials science of particular relevance to photonic applications. Diagnosis is carried out optically, opening up a new approach to characterisation of such catalytic processes generally.  相似文献   

14.
As the fundamental optical properties and novel photophysics of graphene and related two-dimensional(2D) crystals are being extensively investigated and revealed, a range of potential applications in optical and optoelectronic devices have been proposed and demonstrated. Of the many possibilities, the use of 2D materials as broadband, cost-effective and versatile ultrafast optical switches(or saturable absorbers) for short-pulsed lasers constitutes a rapidly developing field with not only a good number of publications, but also a promising prospect for commercial exploitation. This review primarily focuses on the recent development of pulsed lasers based on several representative 2D materials. The comparative advantages of these materials are discussed, and challenges to practical exploitation, which represent good future directions of research, are laid out.  相似文献   

15.
Ultrashort lasers provide an important tool to probe the dynamics of physical systems at very short time-scales, allowing for improved understanding of the performance of many devices and phenomena used in science, technology, and medicine. In addition ultrashort pulses also provide a high peak intensity and a broad optical spectrum, which opens even more applications such as material processing, nonlinear optics, attosecond science, and metrology. There has been a long-standing, ongoing effort in the field to reduce the pulse duration and increase the power of these lasers to continue to empower existing and new applications. After 1990, new techniques such as semiconductor saturable absorber mirrors (SESAMs) and Kerr-lens mode locking (KLM) allowed for the generation of stable pulse trains from diode-pumped solid-state lasers for the first time, and enabled the performance of such lasers to improve by several orders of magnitude with regards to pulse duration, pulse energy and pulse repetition rates. This invited review article gives a broad overview and includes some personal accounts of the key events during the last 20 years, which made ultrafast solid-state lasers a success story. Ultrafast Ti:sapphire, diode-pumped solid-state, and novel semiconductor laser oscillators will be reviewed. The perspective for the near future indicates continued significant progress in the field.  相似文献   

16.
Lasers for materials processing: specifications and trends   总被引:2,自引:0,他引:2  
An overview is given of the types of lasers dominating the field of laser materials processing. The most prominent lasers in this field are the CO2 and the Nd: YAG laser. The domain of CO2 lasers is applications which demand high laser powers (up to 30 kW are available at present), whereas the domain of Nd:YAG lasers is micro-machining applications. In the kilowatt range of laser output power, the two types of lasers are in competition. New diffusion-cooled CO2 laser systems are capable of output laser powers of several kilowatts, with good beam qualities, while still being quite compact. The output power and beam quality of Nd:YAG lasers has been improved in recent years, so that Nd:YAG lasers are now an alternative to CO2 lasers even in the kilowatt range. This is especially true for applications that demand optical fibre transmission of the laser beam, which is possible with Nd:YAG laser light but not with the longerwavelength light emitted by CO2 lasers. The main problem in solid-state lasers such as Nd:YAG is the thermal lensing effect and damage due to thermal stresses. In order to reduce thermal loading, cooling has to be enhanced. Several alternative geometries have been proposed to reduce thermal loading and, by this, thermal lensing effects. There are now slab and tube geometries which allow much higher output powers than the conventionally used laser rods. A very new scheme proposes a thin slab whose cooled side is also used as one of the laser mirrors, so that thermal gradients occur mainly in the direction of the beam propagation and not perpendicular to it, as is the case in the other geometries. As well as CO2 and Nd:YAG lasers, semiconductor laser diodes are very promising for direct use of the emitted light or as pump sources for Nd:YAG and other solid-state lasers. When packaging together thousands of single laser diodes, output powers of several kilowatts can be realized. Major problems are collimation of the highly divergent laser beams and cooling of the laser diode bars.  相似文献   

17.
We investigate the two-dimensional (2D) probe absorption spectrum in a semiconductor quantum well driven by two orthogonal standing-wave lasers. It is found that, due to the position-dependent quantum interference, the 2D spatial distribution of probe absorption spectrum can be easily controlled via adjusting the system parameters. Thus, our scheme shows the underlying probability for the applications in solid-state optic communication and transmission.  相似文献   

18.
高功率超短脉冲激光与新奇物理现象   总被引:1,自引:0,他引:1  
 CPA(Chirped Pulse Amplification)技术,掺钛蓝宝石晶体材料与高功率固体激光器相结合,产生了新一代激光器,把已有高功率固体激光器的脉冲宽度缩短了3~4个数量级,输出功率提高了2~3个数量级,超过1PW,聚焦功率密度高达1021 W/cm2。激光技术这一划时代的进展打开了一个新奇的物理学世界,科学家们观察到了许多意想不到的新现象,也在探索和思考其令人鼓舞的应用前景。  相似文献   

19.
Over the last years, there has been tremendous progress with compact pulsed lasers based on various solid-state gain media, such as crystals and glasses doped with laser-active ions. With the integration of increasingly diverse saturable absorber materials, these small sources are capable of delivering stable pulses with durations as short as femtoseconds and repetition rates exceeding 10 GHz. These promising sources are known as solid-state waveguide lasers, which have become synonymous with miniaturization, integration, and functionality.This article overviews the progress in the development of passively Q-switched and mode-locked solid-state waveguide lasers employing diverse saturable absorbers. The most commonly used laser configurations,state-of-the-art waveguide fabrication techniques, and experimental demonstrations of pulsed waveguide lasers are summarized and reviewed. Selected well-noted topics, which may shape the future directions in this field, are also presented.  相似文献   

20.
高能激光技术进展与面临的挑战   总被引:1,自引:0,他引:1  
苏毅 《物理》2011,40(2)
文章分析和比较了几种高能激光器技术发展现状和面临的挑战,以及各自可能适用的范围.特别对二极管抽运固体激光器和光纤激光器的几种束相干合成方法和光束质量评价方法进行了分析和讨论.二极管抽运固体激光器和光纤激光器近十年来异军突起,被人们看作是继化学激光器后的第二代高能激光器.光纤激光器进展要比二极管抽运固体激光器滞后5到10年.对几十万瓦以上的激光器来说,在相当长的时间内仍然要靠化学激光器.  相似文献   

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