相变异质结(PCH)存储材料相变行为的原位观测

相变存储器(PCM)具有速度快、寿命长等一系列优点.传统的相变存储器在相变过程中会产生蘑菇状的相变层,导致沿电流方向的元素迁移,使器件在多次循环之后失效.相变异质结(phase-change heterostructure,PCH)存储材料通过在相变材料Sb2Te3(ST)中嵌入约束层TiTe2(TT),能够有效降低其...     

科学家制造出超大容量纳米级信息存储材料

法国和瑞士科学家日前开发出一种名为“自动组合结构”的材料制造技术，进而制成新型超大容量的纳米级信息存储材料，每平方厘米的这种材料可存储的信息达到4万亿比特。     

超大容量纳米级信息存储材料问世

法国和瑞士科学家开发出一种名为“自动组合结构”的材料制造技术，进而制成新型超大容量的纳米级信息存储材料，每平方厘米的这种材料可存储的信息达到4万亿比特。     

信息存储材料的现状与未来

信息存储材料的研究与开发直接影响着整个信息技术的发展进程。本文从磁光存储材料，磁存储材料、光存储材料和纳米存储材料四个方面评述了现代信息存储材料应用于电子领域中的现状，并就其前景及今后研究方向进行了讨论。     

当前相变存储材料与器件的特性测量技术

相变存储（phase change memory,PCM）,是一种新兴的非易失性计算机存储器技术,未来将能取代许多应用中的闪存。PCM要比闪存快得多,而且可靠性很高,达到10亿次写入循环,相比之下．闪存的每个区只能写入5000次。PCM还可以缩减到比闪存更小的尺度。本文就论述了PCM器件的技术基础,以及当前相应的特性测试方法。     

光致漂白材料的激光三维信息高密度存储

光信息存储是目前数字化信息存储的主要手段，传统二维光信息存储中存在的不足限制了存储密度及存储容量的进一步提高。基于光致漂白材料的三维光信息存储机理，建立了共焦/双光子扫描荧光显微镜系统。采用一种新型光致漂白芴类衍生物ATFTBAr作为存储材料，利用飞秒激光实现了在该材料上的三维光信息存储和读取。存储层达到四层，每层间距和信息点间距分别达到了10 m 和8 m。对信息点进行了信号强度的识别和对比，详细分析了由于折射率失配所引起的信号串扰问题。研究表明，建立的实验系统和选用的存储材料能够较好地实现三维光信息存储。     

用于非易失性体全息数据存储的光折变材料

全息数据存储系统很久已有大存储容量、短存取时间和高数据传输率的希望。诸如铌酸锂(LiNbO3)之类光折变材料可在适中激光功率下用于全息图记录(图1)。图1　数字全息记录光装置。晶体绕垂直轴转180°,可实现相位共轭读出。其中CCD为电荷耦合器件,L为透镜,I为光阑,RS为转台...     

相变随机存储器材料与结构设计最新进展

介绍了相变随机存储器(PCRAM)的研究现状,包括新型相变材料、热阻层材料和器件结构等.分析了GeSb和SiSb等相变材料具有组分简单、数据保持力好、优良的存储性能等特点,介绍了PCRAM这一新型半导体存储器的基本原理、特点以及国内外有关相变材料、过渡层材料和器件结构设计等方面的研究进展,最后提出了我国发展PCRAM的几点思考.     

可调谐光流控装置实现微粒筛选与存储研究

基于在波导旁边的微环谐振和耦合波导对处倏逝波的光捕获能力,提出了一种由硫族化合物半导体Sb₂Se₃组成的光流控装置,可以通过Sb₂Se₃在非晶态和结晶态之间的相变对装置所实现的功能进行主动调制,使装置能够在单波长输入条件下,实现两种不同的工作状态。采用球形和棒状聚苯乙烯颗粒作为模型系统,其中球形(直径为0.5μm)和棒状(直径为0.5μm,长度为1.5μm)的聚苯乙烯颗粒可以分别模拟金黄色葡萄球菌和杆状大肠杆菌这两种不同的细菌用于实现该装置的形状筛选功能。通过加热Sb₂Se₃到结晶温度(T_C=200℃),使波导和谐振环的材料相变,可以调节装置在存储微纳米粒子、筛选微纳米粒子两种功能之间切换。这可能会为生物分子的形状选择性筛分提供参考,满足新一代芯片实验室技术的要求。     

相变储能材料现状和应用研究

本文主要论述了相变储能材料的分类、性能要求以及应用方面的新进展，并提出了未来的研究发展方向。     

Optically Triggered Synchronous Heat Release of Phase-Change Enthalpy and Photo-Thermal Energy in Phase-Change Materials at Low Temperatures

Phase-change materials (PCMs) are used in several energy recycling utilization systems due to their latent-heat-storage and -release ability. However, the inability of PCMs to release heat at temperatures below their freezing point limits their application in distributed energy utilization systems. This paper reports optically-triggered low-temperature heat release in PCMs based on a solid–liquid phase change (PC) controlled by the trans–cis (E–Z) photo-isomerization of azobenzene. To achieve this, a photo-responsive alkyl-grafted Azo is incorporated into tetradecane (Ted) to create a photo-sensitive energy barrier for the PC. The Azo/Ted composite exhibits controllable supercooling (4.04–8.80 °C) for heat storage and achieves synchronous heat release of PC enthalpy and photo-thermal energy. In addition, the Azo reduces the crystallization of Ted by intercalating into its molecular alignment. Furthermore, under light illumination, the Azo/Ted composite releases considerable heat (207.5 J g⁻¹) at relatively low temperatures (−1.96 to −6.71 °C). The temperature of the annular device fabricated for energy utilization increases by 4 °C in a low-temperature environment (−5 °C). This study will pave the way for the design of advanced distributed energy systems that operate by controlling the energy storage/release of PCMs over a wide range of temperatures.     

Antioxidant-Based Phase-Change Thermal Interface Materials with High Thermal Stability

This work provides phase-change thermal interface materials (TIMs) with high thermal stability and high heat of fusion. They are based on antioxidants mainly in the form of hydrocarbons with linear segments. The thermal stability is superior to paraffin wax and four commercial phase-change materials (PCMs). The use of 98.0 wt.% thiopropionate antioxidant (SUMILIZER TP-D) with 2.0 wt.% sterically half-hindered phenolic antioxidant (GA80) as the matrix and the use of 16 vol.% boron nitride particles as the solid component give a PCM with a 100°C lifetime indicator of 5.3 years, in contrast to 0.95 year or less for the commercial PCMs. The heat of fusion is much higher than those of commercial PCMs; the values for antioxidants with nonbranched molecular structures exceed that of wax; the value for one with a branched structure is slightly below that of wax. The phase-change properties are degraded by heating at 150°C much less than those of the commercial PCMs. The stability of the heat of fusion upon phase-change cycling is also superior. The viscosity is essentially unaffected by heating at 150°C. Commercial PCMs give slightly lower values of the thermal contact conductance for the case of rough (12 μm) mating surfaces, in spite of the lower values of the bond-line thickness.     

Hybrid State Engineering of Phase-Change Metasurface for All-Optical Cryptography

Chalcogenide material Ge₂Sb₂Te₅ (GST) has bistable phases, the so-called amorphous and crystalline phases that exhibit large refractive index contrast. It can be reversibly switched within a nanosecond time scale through applying thermal bias, especially optical or electrical pulse signals. Recently, GST has been exploited as an ingredient of all-optical dynamic metasurfaces, thanks to its ultrafast and efficient switching functionality. However, most of these devices provide only two-level switching functionality and this limitation hinders their application to diverse all-optical systems. In this paper, the method to expand switching functionality of GST metasurfaces to three level through engineering thermo-optically creatable hybrid state that is co-existing state of amorphous and crystalline GST-based meta-atoms is proposed. Furthermore, the novel hologram technique is introduced for providing the visual information that is only recognizable in the hybrid state GST metasurface. Thanks to thermo-optical complexity to make the hybrid state, the metasurface allows the realization of highly secured visual cryptography architecture without the complex optical setup. The phase-change metasurface based on multi-physical design has significant potential for applications such as all-optical image encryption, security, and anti-counterfeiting.     

电子俘获得光存储材料的研究进展

电子俘获存储技术是一种新型的存储技术，有望从存储机制方面突破现有的光存储介质的限制，实现大密度稳定可重复擦写存储，文中详细报道了近年来电子俘获光存储材料的研究进展。着重介绍了电子俘获材料光存储机制，以及各种材料的存储特性，并探讨了存在的问题。     

光盘记录介质研究进展

随着材料科学、光存储技术的发展,国内外对光存储介质的研究不断深入.文章对全息、光谱烧孔、电子俘获、双光子、光致变色材料等光盘记录介质及其存储机理研究进展进行了综述.     

High-Throughput Screening for Phase-Change Memory Materials

Phase change memory (PCM) is an emerging non-volatile data storage technology concerned by the semiconductor industry. To improve the performances, previous efforts have mainly focused on partially replacing or doping elements in the flagship Ge-Sb-Te (GST) alloy based on experimental “trial-and-error” methods. Here, the current largest scale PCM materials searching is reported, starting with 124 515 candidate materials, using a rational high-throughput screening strategy consisting of criteria related to PCM characteristics. In the results, there are 158 candidates screened for PCM materials, of which ≈68% are not employed. By further analyses, including cohesive energy, bond angle analyses, and Born effective charge, there are 52 materials with properties similar to the GST system, including Ge₂Bi₂Te₅, GeAs₄Te₇, GeAs₂Te₄, so on and other candidates that have not been reported, such as TlBiTe₂, TlSbTe₂, CdPb₃Se₄, etc. Compared with GST, materials with close cohesive energy include AgBiTe₂, TlSbTe₂, As₂Te₃, TlBiTe₂, etc., indicating possible low power consumption. Through further melt-quenching molecular dynamic calculation and structural/electronic analyses, Ge₂Bi₂Te₅, CdPb₃Se₄, MnBi₂Te₄, and TlBiTe₂ are found suitable for optical/electrical PCM applications, which further verifies the effectiveness of this strategy. The present study will accelerate the exploration and development of advanced PCM materials for current and future big-data applications.     

Engineered Polymeric Carbon Nitride Additive for Energy Storage Materials: A Review

The ever-increasing demands for high energy density electronics have motivated research on exploring new types of electrode materials featuring mechanical flexibility and electrical storage capability. Of these, polymeric carbon nitride (PCN) has been increasingly studied in regard to electrical energy storage (EES) because of its abundant pyridinic N content, which is beneficial for enhancing electrochemical performance. However, state-of-the-art PCN-based electrode materials for EES are still far from industrial requirements. Herein, the current status of PCN-based materials in batteries and supercapacitors (SCs) is primarily discussed. A particular emphasis is placed on the PCN processing into composite electrode materials, including the defect engineering of pristine PCN and its coupling with other conductive materials to develop heterojunction nanostructures, which is essential for developing highly efficient electrode materials. Moreover, the direct pyrolysis of PCN into N-doped graphene with a tunable N content is introduced and achieves remarkable energy storage performance with superior electronic conductivity. Furthermore, the energy storage mechanisms for batteries and SCs are also highlighted to reveal structure–performance relationship. Finally, this comprehensive review outlines the remaining challenges and strategies for future improvements in PCN-based materials in this emerging field. This review will provide inspiration on developing future PCN-based materials for EES.     

实现海量信息存储密度的最新进展

超高密度（即：海量）信息存储是信息科学发展的基石,本文综述了海量信息存储材料及技术等方面目前的研究进展。     

Materials for Multibit‐per‐Site Optical Data Storage

An approach for multibit‐per‐site optical data storage has been proposed and demonstrated using mesostructured composite films incorporated with uniformly dispersed photoacid generator and pH‐sensitive dye molecules. Upon light illumination, photoacid generator molecules produce acid, which induces a change in the absorption property of pH‐sensitive dye molecules. Because the amount of the generated acid is proportional to the illumination time, the resulting change in the absorption property of mesostructured composite films varies as a function of the illumination time. This function between the absorption property of mesostructured composite films and the illumination time can be used for multibit‐per‐site optical data storage. Recording is performed by using certain discrete values of the illumination time to represent information bits. Reading out is achieved by measuring the absorbance of composite films at a particular wavelength, from which the stored information bits can be determined. In general, N‐bit‐per‐site storage can be realized using 2^N discrete values of the illumination time. This multibit‐per‐site approach for optical data storage is compatible with the current single‐bit‐per‐site technology used for compact disks and digital versatile disks, and will provide significantly larger optical storage capacity. It is also suitable for two‐photon multilayer optical data storage if the photoacid generators and pH‐sensitive dyes are properly designed.