Colossal optical anisotropy in the entire visible spectrum is crucial for advanced photonic applications, enabling precise light manipulation without optical loss across a broad spectral range. Here, we demonstrate that CuAlO2 exhibits colossal optical anisotropy and transparency across the visible spectrum, enabled by its unique three-dimensional O-Cu-O dumbbell structure and two-dimensionally confined excitons. Using mm-sized single crystals, we independently measured ab-plane and c-axis optical properties, revealing maximum birefringence (= 3.67) and linear dichroism (= 5.21), the highest reported to date. CuAlO2 retains birefringence over 0.5 throughout the entire visible range and possesses a wide direct bandgap of 3.71 eV, surpassing the birefringence of commercial anisotropic crystals transparent in the visible spectrum. From the two-dimensional screened hydrogen model and first-principles calculations, we demonstrate that the colossal anisotropy arises from a unique excitonic Cu d-p transition confined to the atomic-thick layer. This colossal optical anisotropy and transparency across the entire visible spectrum makes CuAlO2 a promising candidate for future photonic technologies.
Comments on "Giant Dielectric Response in the One-Dimensional Charge-Ordered Semiconductor (NbSe_{4})_{3}I" and "Colossal Magnetocapacitance and Colossal Magnetoresistance in HgCr_{2}S_{4}"
对“一维电荷有序半导体（NbSe_{4}）_{3}I中的巨介电响应”（D. Staresinic等人，物理修订版信函96，046402（2006））和“Colossal Magnetocapacitance and Colossal Magnetoresistance in HgCr_{2} S_{4}“（S. Weber等人，物理修订信函157202（2006））
REPLY to Comments on "Giant Dielectric Response in the One-Dimensional Charge-Ordered Semiconductor (NbSe4)3I" and "Colossal Magnetocapacitance and Colossal Magnetoresistance in HgCr2S4" (cond-mat/0607500)
Colossal magneto-excitonic effects in 2D van der Waals magnetic semiconductor CrSBr
Faculty of Physics, University of Warsaw（华沙大学物理学院）；Institute of Physics, University of Muenster（明斯特大学物理研究所）；Faculty of Fundamental Problems of Technology, Wrocław University of Science and Technology（弗罗茨瓦夫科技大学基础技术学院）；Department of Inorganic Chemistry, University of Chemistry and Technology Prague（布拉格化工大学无机化学系）；LNCMI, UPR 3228, CNRS, EMFL, Université Grenoble Alpes（格勒诺布尔阿尔卑斯大学CNRS电磁场与物质相互作用实验室）
Sr$_{0.9}$K$_{0.1}$Zn$_{1.8}$Mn$_{0.2}$As$_{2}$: a ferromagnetic semiconductor with colossal magnetoresistance
采用电荷和自旋解耦掺杂方法合成了（Sr，K）（Zn，Mn）$_{2}$ As $_{2}$.它具有六方CaAl $_{2}$ Si $_{2}$型结构，其中（Zn，Mn）$_{2}$ As $_{2}$层形成蜂窝状网络。磁化强度测试表明，样品发生了铁磁转变，居里温度为12 K，转变相为\revision{magnetic moment reaches about 1.5 $μ_{B}$/Mn under $μ_0H$ = 5 T and $T$ = 2 K}。在低场（$μ_0H$ = 0. 1 T）下，$-$的磁电阻率高达38%，而在低场（$μ_0H$ = 5 T）下，$-$的磁电阻率高达99. 8%，其磁电阻率定义为$[ρ(H)-ρ(0)]/ρ(0)$.巨磁电阻效应可以用Anderson局域化理论来解释。
Minimizing propagated density errors of atomic core-electron for simultaneously accurate bandgaps and lattice constants in closed-shell Copper semiconductors
Key Lab of advanced optoelectronic quantum architecture and measurement (MOE), and School of Interdisciplinary Science, Beijing Institute of Technology（北京理工大学光电量子架构与测量教育部重点实验室，交叉科学学院）；Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute（伦斯勒理工学院物理、应用物理和天文学系）
Efficient and Robust p-type Transistor based on Ultra-wide-bandgap Semiconductor
Macau University of Science and Technology（澳门科技大学）；Zhuhai MUST Science and Technology Research Institute（珠海澳门科技大学研究院）；School of Physics and Astronomy, Monash University（蒙纳士大学物理与天文学院）；Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University（南洋理工大学物理与数学科学学院物理与应用物理部）；Department of Materials Science & Engineering, Monash University（蒙纳士大学材料科学与工程系）；Faculty of Materials Science and Engineering, Kunming University of Science and Technology（昆明理工大学材料科学与工程学院）；Department of Electrical and Electronic Engineering, The University of Melbourne（墨尔本大学电气与电子工程系）；School of Science, RMIT University（皇家墨尔本理工大学理学院）；Princeton Plasma Physics Laboratory（普林斯顿等离子体物理实验室）；Bio21 Institute, The University of Melbourne（墨尔本大学生物21研究所）；Research School of Chemistry, Australian National University（澳大利亚国立大学化学研究学院）；Shanghai Key Laboratory of High Temperature Superconductors, Department of Physics, Shanghai University（上海大学物理系高温超导重点实验室）；Centre for Materials Science, School of Chemistry and Physics, Queensland University of Technology（昆士兰科技大学化学与物理学院材料科学中心）；Macao Institute of Materials Science and Engineering (MIMSE), Faculty of Innovation Engineering, Macau University of Science and Technology（澳门科技大学创新工程学院澳门材料科学与工程研究所）；School of Electrical and Electronic Engineering, Nanyang Technological University（南洋理工大学电气与电子工程学院）
2D ferroelectric narrow-bandgap semiconductor Wurtzite' type alpha-In2Se3 and its silicon-compatible growth
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences（中国科学院金属研究所沈阳材料科学国家实验室）；School of Materials Science and Engineering, University of Science and Technology of China（中国科学技术大学材料科学与工程学院）；School of Physical Science and Technology, Jiangsu Key Laboratory of Frontier Material Physics and Devices, Soochow University（苏州大学江苏省前沿材料物理与器件重点实验室物理科学与技术学院）；Collaborative Innovation Center of Extreme Optics, Shanxi University（山西大学极端光学协同创新中心）；Center for Quantum Matter, School of Physics, Zhejiang University（浙江大学物理学院量子物质研究中心）；Department of Mechanical Engineering, The University of Hong Kong（香港大学机械工程系）
本文用一种快速、实用的方法计算了半导体合金的带隙和能带弯曲参数。该方法是一个介电缩放近似的基础上，一个近似。它增加了一个能移的带隙所提供的局域密度近似（LDA）的密度泛函理论（DFT）。能量位移由高频介电常数的倒数加权的材料无关常数组成。该方法的显著特点是通过紧束缚线性松饼-锡轨道（TB-LMTO）的格林函数（GF）在原子球近似（ASA）下快速计算合金的介电常数。当将其应用于高度失配的半导体合金（HMA）（如Zn Te $_x$ Se $_{1-x}$）时，该方法提供了与用LDA计算的带弯曲参数不同的带弯曲参数，这是由于高频介电常数也表现出弯曲。
Reversible Fluorination of Graphene: towards a Two-Dimensional Wide Bandgap Semiconductor
我们报告了石墨烯氟化物的合成和证据，石墨烯是一种二维宽带隙半导体。氟化石墨烯表现出六方晶序和强绝缘行为，在室温下电阻超过10 G $Ω$。氟化石墨烯中的电子输运通过由于带隙中的局域态的存在而在二维中的可变范围跳跃来很好地描述。通过还原氟化石墨烯获得的石墨烯是高度导电的，在室温下表现出小于100 k $Ω$的电阻率。我们的方法提供了一种新的途径，可逆工程的能带结构和导电性的石墨烯的电子和光学应用。
Benchmarking bandgap prediction in semiconductors under experimental and realistic evaluation settings
Centre for Machine Intelligence, University of Sheffield（智能研究中心，谢菲尔德大学）；School of Computer Science, University of Sheffield（计算机科学学院，谢菲尔德大学）；Climate Office, European Space Agency（气候办公室，欧洲航天局）；School of Mathematical and Physical Sciences, University of Sheffield（数学与物理科学学院，谢菲尔德大学）；School of Chemical, Materials and Biological Engineering, University of Sheffield（化学、材料与生物工程学院，谢菲尔德大学）
Colossal low-field negative magnetoresistance in CaAl$_{2}$Si$_{2}$-type diluted magnetic semiconductors (Ba,K)(Cd,Mn)$_{2}$As$_{2}$
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所凝聚态物理国家实验室）；Collaborative Innovation Center of Quantum Matter（量子物质协同创新中心）
Direct growth of crystalline spinel GaON films: A wide-bandgap mixed-anion semiconductor
State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Physics and Optoelectronic Engineering, Shenzhen University（深圳大学物理与光电工程学院射频异构集成国家重点实验室）；Physics Department, The Hong Kong University of Science and Technology（香港科技大学物理系）
