Ternary alloys of Ge-Sb-Te (GST) have been extensively studied due to their unique ability display a reversible change in their phase upon stimulation by optical pulses i.e., amorphous (a-GST) to crystalline (c-GST) and vice-versa. The two phases exhibit remarkably different electrical and optical properties like conductivity, reflectivity, refractive index and optical loss, this coupled with their high phase switching speeds, low power phase switching, large measurable optical and electrical contrast, and phase stability makes GST alloys stand out from other phase change materials (PCM). GST alloys have already found extensive use in optical disks and electronic memories due to their non-volatility and zero static power consumption, but the precise mechanism of the phase change is not clearly understood. The phase change mechanism has usually been attributed to the optical pulse, usually a high power short pulse laser, heating up the c-GST alloy to above its melting temperature (Tm) after which, if it is cooled rapidly enough to below the glass transition temperature (Tg), the atoms are fixed in place due to the drastic reduction in their mobility, resulting in a phase which exhibits structure similar to a frozen liquid and lacks long range order i.e. amorphous. When heated above Tg with an intermediate power laser pulse for a significant amount of time, then this favors the shift back to the energetically favorable crystalline phase. With the growing interest in next generation data storage technology for photonic and neuromorphic computing, the research into understanding and improving the properties of GST alloys has also been rekindled. In this term paper we hope to investigate and gain a deeper understanding and appreciation of the kinetics and underlying atomistic mechanism of this phase transition from c-GST to a-GST and vice-versa which is only now becoming clearer.
Optimizing Tc in the (Mn,Cr,Ga)As and (Mn,Ga)(As,P) Ternary Alloys
我们探索了两种可能的方法来提高稀磁半导体Mn $_{0.08}$ Ga $_{0.92}$ As的临界温度$T_c$。在双交换和RKKY图片的背景下，三元合金Mn $_{x}$ Cr $_{0.08-x}$ Ga $_{0.92}$ As和Mn $_{0.08}$ Ga $_{0.92}$ As $_y$ P $_{1-y}$可能预期具有比伪二元Mn $_{0.08}$ Ga $_{0.92}$ As更高的$T_c$。为了测试是否从模型图片的预期得到证实，我们采用线性响应理论内的局部密度近似搜索理论上更高的临界温度在这些三元合金。我们的研究结果表明，无论是与Cr共掺杂Mn，也没有合金化的P与砷改善$T_c$。发现与Cr合金化对$T_c$有害。Mn $_{0.08}$ Ga $_{0.92}$ As $_y$ P $_{1-y}$显示出$T_c$对$y$的几乎线性依赖性。
Tunable magnetization damping in transition metal ternary alloys
我们表明，坡莫合金，Ni 80 Fe 20（"Py“），磁化阻尼，可以充分提高，以减少后切换磁化旋进到一个可接受的水平，通过与过渡金属锇（Os）合金化。阻尼单调增加后，提高的Os-浓度在Py，至少高达9%的Os。其他的影响与Os合金化的抑制磁化和增强面内各向异性。在与本研究中包括的五种其他过渡金属（4d元素：Nb、Ru、Rh; 5d元素：Ta、Pt）合金化后，磁化阻尼也显著增加，但从未像与Os合金化那样强烈。
High-dielectric constant and wide band gap inverse silver oxide phases of the ordered ternary alloys of SiO$_{2}$, GeO$_{2}$ and SnO$_{2}$
高介电常数和宽带隙氧化物具有重要的技术应用。具有与硅的晶格常数相容性的结晶氧化物多晶型物是特别期望的。最近报道的一种候选物是SiO $_2$的反氧化银相。第一性原理研究了该体系及其等价物GeO $_{2}$、SnO $_{2}$以及它们的三元合金。在密度泛函理论的框架下，采用广义梯度近似和局域密度近似（LDA）计算了它们的结构性质、弹性常数和电子能带结构.为了检查这些材料的稳定性，声子色散曲线计算表明，GeO $_{2}$和SnO $_{2}$具有负声子分支，而它们的三元合金Si $_{0.5}$ Ge $_{0.5}$ O $_{2}$，Si $_{0.5}$ Sn $_{0.5}$ O $_{2}$和Ge $_{0.5}$ Sn $_{0.5}$ O $_{2}$在LDA内都是稳定的，具有10至20之间的介电常数。此外，Si $_{0.5}$ Ge $_{0.5}$ O $_{2}$的晶格常数实际上与Si（100）表面相同。计算了稳定材料的$GW$带隙，其恢复了宽带隙值以及它们的高介电常数。
Investigation of ideal shear strength of dilute binary and ternary Ni-based alloys using first-principles calculations, CALPHAD modeling and correlation analysis
Comprehensive Mapping of Tracer Diffusivities Across Composition Space in Ternary NiAlTi and Quinary NiCoFeAlTi High-Entropy Alloy Using Diffusion Couple Experiments and Physics Informed Neural Network Inversion
Indian Institute of Science（印度科学学院）；Indian Institute of Technology, Hyderabad（印度理工学院海德拉巴分校）
Hybrid-Functional Calculations of Electronic Structure and Phase Stability of MO (M = Zn, Cd, Be, Mg, Ca, Sr, Ba) and Related Ternary Alloy M$_x$Zn$_{1-x}$O
Thermal conductivity of ternary III-V semiconductor alloys: The role of mass difference and long-range order
采用平衡分子动力学和优化的Albe-Tersoff经验原子间相互作用势，研究了三元砷化物（III-As）半导体合金的热输运.现有的二元铝砷，砷化镓和铟砷的潜力进行了优化，以获得准确的声子色散和温度依赖性的热导率。三元III-V族的热输运计算通常采用虚拟晶体近似（VCA），其中结构被假定为随机合金，所有III族原子（阳离子）被视为具有有效加权平均质量。在这里，我们表明，显式处理原子质量是至关重要的，显式原子质量得到的热导率与平均VCA阳离子质量得到的值有很大不同。阳离子质量之间的差异越大，热导率的VCA预测越差。在VCA中的随机合金假设也受到挑战，因为X射线衍射和透射电子显微镜显示在InGaAs，InAlAs和GaAlAs外延层中的顺序。我们计算了三种常见类型的顺序[CuPt-B，CuAu-I，和三周期-A（TPA）]的热导率，并表明，实验结果为In $_{0.53}$ Ga $_{0.47}$ As和In $_{0.52}$ Al $_{0.48}$ As，这是晶格匹配的InP衬底，可以重现在分子动力学模拟与2%和8%的随机无序，分别。根据我们的研究结果，在三元III-As合金的热输运似乎是由质量差散射，这是更明显的比VCA建议，和长程序，这些合金支持之间的竞争。
On the compressibility of the transition-metal carbides and nitrides alloys Zr_xNb_{1-x}C and Zr_xNb_{1-x}N
采用第一性原理全势线性缀加平面波方法，在局域密度近似下研究了岩盐结构中的4d过渡金属碳化物（ZrC，NbC）和氮化物（ZrN，NbN）及其三元合金。这些材料非常重要，因为它们具有有趣的机械和物理特性，这使它们适用于许多技术应用。在这里，通过使用一个简单的理论模型，我们估计的体积模量的三元合金Zr $_x$ Nb $_{1-x}$ C和Zr $_x$ Nb $_{1-x}$ N的体积模量的终端成员单独。计算结果与第一性原理计算的结果相当。
Hydrogen permeability prediction in palladium alloys and virtual screening of B2-phase stabilized Pd(100-x-y)CuxMy ternary alloys using machine learning
Institute of Science Tokyo（东京科学大学）；Dongguk University（东国大学）
Pulsed thermal deposition of binary and ternary transition metal dichalcogenide monolayers and heterostructures
过渡金属二硫属化物（TMDC）在光子器件、光电器件或谷电子器件中的应用需要在单一工艺中生长不同材料的连续单层、异质结构和合金。我们提出了一种简便的脉冲热沉积方法，它提供了精确的控制层厚度和化学计量的二维系统。该方法的通用性被证明在三元单层的钼$_{1-x}$ W $_{x}$ S $_{2}$和异质结构相结合的金属TaS $_{2}$和半导体MoS $_{2}$层。制备的三元单分子膜覆盖了$x$ = 0. 1、无相分离。带隙工程和控制的自旋轨道耦合强度的吸收和光致发光光谱证明。垂直异质结构的生长没有相互混合。清洁和原子突变界面的形成是由高分辨率透射电子显微镜证明。由于金属组分以及硫族化物都是热蒸发的，因此可以制备复杂的合金和异质结构。
