Article
Materials Science, Multidisciplinary
Debajit Deb, R. J. Choudhary, S. M. Yusuf, J. N. Roy, P. Dey
Summary: We investigated the electrical transport response of (100-x)%ZnO-x%rGO/La0.7Sr0.3MnO3 (LSMO)/ITO heterostructure devices under light and magnetic field at room temperature. The magnetoresistance (MR) response showed negative and positive behavior for bare and composite devices, respectively, due to spin-dependent scattering in the LSMO space charge region. The bias current in bare devices exhibited defect-induced suppression with light, resulting in an overall decrease in device current at low fields. However, at high fields, the bias current started increasing with light, leading to a reversal of photosensitivity from negative to positive.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yajuan Zhao, Zhigang Yin, Xingxing Li, Maoyuan Zheng, Yong Cheng, Jingbi You, Jinliang Wu, Xingwang Zhang
Summary: This study reports the stabilization of the metastable tetragonal phase of BiFeO3 on the highly anisotropic ZnO(11-20) surface. Heteroepitaxy generates anisotropic misfit strains that are powerful in controlling the energy balance of competing phases, favoring the formation of tetragonal BiFeO3. The integration of thick tetragonal BiFeO3 films with ZnO has important implications for oxide electronics.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Chemistry, Multidisciplinary
Sagnik Das, Uttam Kumar Ghorai, Rajib Dey, Chandan Kumar Ghosh, Mrinal Pal
Summary: This paper reports the successful tuning of defect-mediated blue phosphorescence of ZnO nanopowders by annealing at different temperatures, resulting in changes in intensity, shade, and color temperature. Multiple characterization techniques were used to examine the microstructural, compositional, and band-structure details, and optical properties of the samples were studied through PL and tau-PL spectroscopy.
Article
Physics, Multidisciplinary
Michikazu Kobayashi, Naoko Nakagawa, Shin-ichi Sasa
Summary: The violation of the assumption of local equilibrium thermodynamics for phase coexistence in heat conduction is numerically analyzed using the Hamiltonian Potts model in two dimensions. It is observed that the temperature of the interface between ordered and disordered states deviates from the equilibrium transition temperature, indicating the stabilization of metastable states by the influence of a heat flux. Furthermore, it is found that the deviation can be described by a formula proposed in an extended framework of thermodynamics.
PHYSICAL REVIEW LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Tanusree Saha, Arindam Pramanik, Barbara Ressel, Alessandra Ciavardini, Fabio Frassetto, Federico Galdenzi, Luca Poletto, Arun Ravindran, Primoz Rebernik Ribic, Giovanni De Ninno
Summary: This study investigates the photoinduced transient phase and ground state recovery dynamics in the complex material 1T-TaS2 using femtosecond time- and angle-resolved photoemission spectroscopy. The results reveal similarities between the band structures of the transient and equilibrium phases, with evidence for coexistence of the Mott insulating and metallic phases. The study also finds that the recoveries of Mott and CDW orders begin simultaneously, highlighting their coupling. Additionally, a metastable phase is observed during the recovery process, which is driven by the CDW lattice order.
Article
Chemistry, Multidisciplinary
Maria L. K. Viitaniemi, Christian Zimmermann, Vasileios Niaouris, Samuel H. D'Ambrosia, Xingyi Wang, E. Senthil Kumar, Faezeh Mohammadbeigi, Simon P. Watkins, Kai-Mei C. Fu
Summary: Utilizing indium donors, this study demonstrates the favorable optical and electron spin properties in ZnO nanowires. The research shows that the optical line width of single nanowires is comparable to bulk single-crystalline ZnO and successfully achieves spin initialization and observation of coherent population trapping.
Article
Materials Science, Multidisciplinary
Dooyong Lee, Sehwan Song, Taewon Min, Hyegyeong Kim, Jiwoong Kim, Seonghoon Han, Jong-Seong Bae, Jisung Lee, Yoosuk Kim, Jouhahn Lee, Jae Hyuck Jang, Jaekwang Lee, Sungkyun Park
Summary: Oxygen point defects play a crucial role in stabilizing the M3-VO2 phase, resulting in higher phase transition temperature and sharper phase transition characteristics.
APPLIED MATERIALS TODAY
(2022)
Article
Physics, Applied
Andrew Venzie, Amanda Portoff, Michael Stavola, W. Beall Fowler, Jihyun Kim, Dae-Woo Jeon, Ji-Hyeon Park, Stephen J. Pearton
Summary: alpha-Ga2O3, similar to alpha-Al2O3 in structure, has a larger bandgap energy, making it attractive for devices requiring wider bandgaps. Studies on O-H and O-D centers in alpha-Ga2O3 implanted with H+ and D+ ions, along with complementary theory, suggest that H complexes with Ga vacancies, similar to H trapped by Al vacancies in alpha-Al2O3. Theoretical analysis reveals that V-Ga and V-Al defects in alpha-Ga2O3 and alpha-Al2O3 have shifted equilibrium configurations, similar to V-Ga in beta-Ga2O3. However, the addition of H results in the lowest energy state being a complex with H trapped at an unshifted vacancy in both alpha-Ga2O3 and alpha-Al2O3.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Chaopeng Zhao, Weishan Yan, Wangyang Zhang, Duo Liu
Summary: This study demonstrates that phonons can promote the relaxation of metastable centers in ZnO through the electron-phonon interaction. The findings provide valuable guidance for the development of novel quantum and photoactive devices.
Article
Chemistry, Applied
Sikder Ashikuzzaman Ayon, Sajjad Hasan, Md Muktadir Billah, Sadiq Shahriyar Nishat, Alamgir Kabir
Summary: In this study, undoped and Sm3+ doped ZnO nanoparticles were synthesized using a modified sol-gel route. The opto-structural properties of the doped nanoparticles were investigated both experimentally and theoretically. The results showed complete dissolution of Sm3+ ions into the ZnO lattice and morphological changes with doping. Increasing the dopant quantity resulted in a redshift of the nanoparticles, a decrease in bandgap, and increased absorption in the visible range. Photoluminescence spectroscopy revealed the recombination rate of electron-hole pairs. Theoretical analysis using density functional theory was also performed. The study provides insight into the structural properties of the synthesized nanoparticles and their enhanced photocatalytic activity.
JOURNAL OF RARE EARTHS
(2023)
Article
Materials Science, Multidisciplinary
Xuan Chen, Jin Li, Xiangjia Liu
Summary: The study found that decreasing the concentration of NaOH led to a decrease in the crystallinity of ZnO, an increase in internal defects, and an increase in visible light emission intensity. The addition of NiS@NiO significantly enhanced the emission intensity and resulted in the same type of luminescence characteristics for all ZNN composites.
Article
Chemistry, Physical
Tongshan Lu, Jinpeng Lv, Chenghua Wang
Summary: Hydrogenation significantly improves the radiation stability of Ga2O3, while only slightly affects ZnO and TiO2. Oxygen deficient defects and grain size play vital roles in tuning the radiation tolerance of metal oxide semiconductors.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Deng-Hua Li, Zhen-Yi Jiang, Yan-Min Lin, Ji-Ming Zheng
Summary: The study used first-principles DFT+U method to investigate the doping effects of Sn/Pb atoms in TiO2 anatase phase. Results showed that Sn atoms preferentially replace internal titanium atoms, while Pb atoms are more likely to substitute surface titanium atoms. The presence of tin ions and lead ions creates electron traps, delaying the recombination time of photogenerated electron-hole pairs and playing a key role in photocatalytic performance.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Ruifeng Song, Jingming Yao, Ruonan Xu, Zhixuan Li, Xinlin Yan, Chuang Yu, Zhigao Huang, Long Zhang
Summary: A stable interface and preventing dendrite-growth are crucial for the long-life of solid-state Li batteries using sulfide-based solid electrolytes (SEs) and Li metal anodes. This study reports a strategy using Si doping in Cl-rich argyrodites that enables self-engineered metastable decomposition, leading to the realization of these two factors simultaneously. The metastable Cl atoms react with Li atoms, depleting locally deposited/grown Li crystal nuclei and generating electrically insulated LiCl shells at the grain boundaries. These shells prevent Li redeposition and act as self-protective layers, enabling an ultra-long life ASSLB with Li metal anodes under high current densities at room temperature.
ADVANCED ENERGY MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Jinpeng Lv, Xiangyu Wen, Zhenhua Zhou, Bo Zhou, Hexiang Han
Summary: This study systematically investigates the effects of O+ and N+ irradiation damage on ZnO bulk crystals, revealing the differences in ZnO damage induced by different ion irradiations. Our findings show that N+ irradiation results in a significant increase in electron concentration while O+ irradiation leads to the emergence of VZn related acceptors. Additionally, we observe the first observation of 450 nm VZn emission created by O+ irradiation.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
