Article
Multidisciplinary Sciences
Aditya Sood, Xiaozhe Shen, Yin Shi, Suhas Kumar, Su Ji Park, Marc Zajac, Yifei Sun, Long-Qing Chen, Shriram Ramanathan, Xijie Wang, William C. Chueh, Aaron M. Lindenberg
Summary: Understanding the pathways and time scales underlying electrically driven insulator-metal transitions is vital for uncovering the fundamental limits of device operation. By using stroboscopic electron diffraction, researchers discovered an electrically triggered, isostructural state that forms transiently on microsecond time scales and established electrical excitation as a route for uncovering nonequilibrium and metastable phases in correlated materials. This metastable phase is similar to that formed under photoexcitation within picoseconds, suggesting a universal transformation pathway.
Article
Physics, Applied
Raju B. Naik, Divya Verma, Viswanath Balakrishnan
Summary: This work investigates the variation in threshold voltage of memristor behavior in tungsten-doped VO2 crystals. The effects of chemical doping on the metal-insulator transition are studied through Raman spectroscopy and differential scanning calorimetry. Additionally, the bi-polar threshold switching of VO2 memristor behavior is demonstrated in microcrystals with different contents of tungsten.
APPLIED PHYSICS LETTERS
(2022)
Article
Multidisciplinary Sciences
Ge Li, Donggang Xie, Hai Zhong, Ziye Zhang, Xingke Fu, Qingli Zhou, Qiang Li, Hao Ni, Jiaou Wang, Er-jia Guo, Meng He, Can Wang, Guozhen Yang, Kuijuan Jin, Chen Ge
Summary: This study reports a non-volatile multi-level control of vanadium dioxide (VO2) films through oxygen stoichiometry engineering, which can be used for bioinspired neuromorphic vision components. A proof-of-principle neuromorphic ultraviolet sensor with integrated sensing, memory, and processing functions at room temperature is demonstrated, showing its potential application in artificial vision systems.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Jiyu Xu, Daqiang Chen, Sheng Meng
Summary: Photoexcitation has been proven as an efficient way to trigger phase transitions in strongly correlated materials. However, the atomistic mechanisms behind the structural phase transitions (SPTs) and electronic insulator-metal transitions (IMTs) in VO2 have been controversial. This study clarifies some key controversies and provides insights into the underlying atomistic processes and decoupling nature of photoinduced SPT and IMT in nonequilibrium states.
Article
Materials Science, Multidisciplinary
Carl Willem Rischau, Xu He, Giacomo Mazza, Stefano Gariglio, Jean-Marc Triscone, Philippe Ghosez, Javier del Valle
Summary: We investigated the effects of oxygen isotope on the metal-insulator transition of VO2. By synthesizing V16 O2 and V18 O2 crystals using an alternative method, we observed a 1%-3% phonon softening and a 1.3 K increase in the metal-insulator transition temperature for V18 O2. Calculation and density functional theory confirmed that this shift is due to changes in the lattice internal energy. Our findings highlight the importance of lattice dynamics in determining the electronic transition temperature and the strong coupling between electronic and structural degrees of freedom at the transition.
Article
Chemistry, Physical
Jean-Louis Victor, Manuel Gaudon, Giorgio Salvatori, Olivier Toulemonde, Nicolas Penin, Aline Rougier
Summary: In this study, highly crystallized Fe-doped VO2 powders were successfully synthesized using a carbo-thermal reduction process, with Fe doping impacting the crystal structure and phase transition of VO2. The transition temperature was significantly increased to 134 degrees C, marking a breakthrough in VO2-type thermochromic materials.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Dooyong Lee, Taewon Min, Jiwoong Kim, Sehwan Song, Jisung Lee, Haeyong Kang, Jouhahn Lee, Deok-Yong Cho, Jaekwang Lee, Jae Hyuck Jang, Sungkyun Park
Summary: The study found that octahedral symmetry in VO2 can control its IMT characteristics by changing orbital occupancy, and monoclinic VO2 with high octahedral symmetry exhibits bandwidth-controlled IMT characteristics.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Physics, Applied
G. M. Hunt, J. A. Miragliotta, J. Ginn, A. P. Warren, D. B. Shrekenhamer
Summary: This article introduces a passive and adaptive thermal management system that utilizes the properties of VO2 material to provide insulation at low temperatures and heat dissipation at high temperatures, thereby reducing energy consumption. By doping VO2 with high valence tungsten, the transition temperature can be close to room temperature. By carefully engineering the thickness and doping of the VO2 layer in the multilayer film, a 50% emissive contrast was maintained across the 8-13 μm spectral region.
APPLIED PHYSICS LETTERS
(2023)
Article
Multidisciplinary Sciences
Shaobo Cheng, Min-Han Lee, Richard Tran, Yin Shi, Xing Li, Henry Navarro, Coline Adda, Qingping Meng, Long-Qing Chen, R. C. Dynes, Shyue Ping Ong, Ivan K. Schuller, Yimei Zhu
Summary: The study successfully characterized the structural stochasticity of vanadium dioxide (VO2) during phase transition and revealed its anisotropy through different methods. By evaluating statistical cycle-to-cycle variation and demonstrating the stochastic nature of volatile resistive switching, the research laid a foundation for understanding the key material applications of VO2 in neuromorphic computing.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Materials Science, Multidisciplinary
Yongchang Ma, Rui Chen, Yajun Li, Cuimin Lu, Chenguang Zhang
Summary: We propose a model to estimate the energy barrier responsible for the hysteresis of the thermally driven Mott phase transition and validate the model with experimental data. For heating, the resistance in VO2 films exhibits step-like changes, forming multiple nonvolatile states, while no significant changes occur during cooling. The memory ability is attributed to the structure of the metal and insulator domains.
Article
Chemistry, Multidisciplinary
Mengxia Qiu, Wanli Yang, Peiran Xu, Tiantian Huang, Xin Chen, Ning Dai
Summary: This study presents polymorphous VO2 thin films with coexistent VO2 (M) and VO2 (B) phases and phase-dependent insulator-metal transition (IMT) behaviors. The presence of VO2 (B) phases may induce lattice distortions in VO2 (M), resulting in widened plane spacing of (011)(M) in the VO2 (M) phase and shifted V-V and V-O vibrations. The coexisting VO2 (B) phases promote the IMT temperature of the polymorphous VO2 thin films.
Article
Chemistry, Multidisciplinary
Chung T. Ma, Salinporn Kittiwatanakul, Apiprach Sittipongpittaya, Yuhan Wang, Md Golam Morshed, Avik W. Ghosh, S. Joseph Poon
Summary: The ability to manipulate spins in magnetic materials is crucial in spintronics device design. This study demonstrates the tunable magnetic properties of TbFeCo on VO2/TiO2 films using strain-induced effects. Through anomalous Hall effect measurements, it is confirmed that the metal-insulator transition of VO2 can alter the magnetic anisotropy and magnetization of TbFeCo. This research lays the foundation for controlling magnetic properties through phase transitions.
Article
Optics
Xue Chang, Jiang Li, Jian Mu, Chun-Hao Ma, Wanxia Huang, Hong-Fu Zhu, Qiao Liu, Liang-Hui Du, Sen-Cheng Zhong, Zhao-Hui Zhai, Sujit Das, Yen-Lin Huang, Gang-Bei Zhu, Li-Guo Zhu, Qiwu Shi
Summary: This study investigated the THz modulation properties of epitaxial VO2 films on a flexible mica substrate under different uniaxial strains. It was found that the THz modulation depth increases under compressive strain and decreases under tensile strain, and the phase-transition threshold depends on the uniaxial strain. The rate of phase transition temperature change was approximately 6 degrees C/% under temperature-induced phase transition. The optical trigger threshold in laser-induced phase transition decreased by 38.9% under compressive strain but increased by 36.7% under tensile strain. These findings demonstrate the uniaxial strain-induced low-power triggered THz modulation and provide new insights for applying phase transition oxide films in THz flexible electronics.
Review
Chemistry, Multidisciplinary
Parker Schofield, Adelaide Bradicich, Rebeca M. Gurrola, Yuwei Zhang, Timothy D. Brown, Matt Pharr, Patrick J. Shamberger, Sarbajit Banerjee
Summary: Future-generation neuromorphic computing aims to emulate the functions of neurons and synapses in the human brain in order to overcome the limitations of current computing architectures. This article discusses VO2 as an attractive material candidate and strategies for tuning its transformation characteristics. The importance of mechanistic understanding and inverse design is emphasized.
ADVANCED MATERIALS
(2023)
Article
Physics, Applied
Stephanie M. Bohaichuk, Suhas Kumar, Mahnaz Islam, Miguel Munoz Rojo, R. Stanley Williams, Gregory Pitner, Jaewoo Jeong, Mahesh G. Samant, Stuart S. P. Parkin, Eric Pop
Summary: Oscillatory devices are important in biomimetic neuronal spiking computing systems, but understanding their time scales is challenging due to the influence of external circuitry. In this study, we demonstrate the challenges using a sub-100-nm VO2 Mott oscillator with a nanogap cut in a metallic carbon nanotube electrode. Despite its nanoscale thermal volume, external parasitics result in orders-of-magnitude slower dynamics. We discuss methods for determining when measurements are dominated by extrinsic factors and the conditions for observing intrinsic oscillation frequencies.
PHYSICAL REVIEW APPLIED
(2023)
Article
Materials Science, Multidisciplinary
Sabine N. Neal, Kenneth R. O'Neal, Amanda Haglund, David G. Mandrus, Hans A. Bechtel, G. Lawrence Carr, Kristjan Haule, David Vanderbilt, Heung-Sik Kim, Janice L. Musfeldt
Summary: Using synchrotron-based near-field infrared spectroscopy and lattice dynamics calculations, the vibrational response of CrPS4 in different thicknesses was investigated. The mode pattern showed a specific space group characteristic with no symmetry crossover as a function of layer number, and non-monotonic frequency shifts were observed. In contrast to MnPS3, CrPS4's vibrational response is sensitive to interlayer motion and displacement patterns.
Article
Materials Science, Coatings & Films
Eduardo Bonini Guedes, Tobias Willemoes Jensen, Muntaser Naamneh, Alla Chikina, Ramus T. Dahm, Shinhee Yun, Francesco M. Chiabrera, Nicholas C. Plumb, J. Hugo Dil, Ming Shi, Dennis Valbjorn Christensen, Walber Hugo Brito, Nini Pryds, Milan Radovic
Summary: By combining experimental observations and theoretical calculations, this study investigates the surface electronic structure of bent SrTiO3 wafers. It is found that even a small external strain of 0.1% can alter the energy of in-gap states. Furthermore, calculations show that larger strain values significantly affect the orbital splitting of the surface conduction band. This research highlights the ability of strain to tailor the electronic properties of STO surfaces and interfaces.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Review
Chemistry, Physical
J. D. Denlinger, J-S Kang, L. Dudy, J. W. Allen, Kyoo Kim, J-H Shim, K. Haule, J. L. Sarrao, N. P. Butch, M. B. Maple
Summary: The study investigates the relationship between narrow-band states and bulk Fermi surface topology in URu2Si2 using ARPES mapping of the electronic structure. It reveals the interaction between these states and other band states, and provides insight into the properties and temperature evolution of high symmetry points and nested Fermi-edge states, supporting the understanding of the hidden order transition.
ELECTRONIC STRUCTURE
(2022)
Article
Materials Science, Multidisciplinary
K. Park, M. O. Yokosuk, M. Goryca, J. J. Yang, S. A. Crooker, S-W Cheong, K. Haule, D. Vanderbilt, H-S Kim, J. L. Musfeldt
Summary: In this study, by combining magneto-optical spectroscopy and first-principles calculations, we reveal the nonreciprocity and formation mechanism of Ni3TeO6 in the toroidal geometry. Additionally, we demonstrate the deterministic control of nonreciprocal directional dichroism in Ni3TeO6. These findings are of great significance for the development of photonics applications that utilize the unique symmetry characteristics of materials.
NPJ QUANTUM MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Aifeng Wang, Lijun Wu, Qianheng Du, Muntaser Naamneh, Walber Hugo Brito, A. M. Milinda Abeykoon, Wojciech Radoslaw Pudelko, Jasmin Jandke, Yu Liu, Nicholas C. Plumb, Gabriel Kotliar, Vladimir Dobrosavljevic, Milan Radovic, Yimei Zhu, Cedomir Petrovic
Summary: The nanoscale inhomogeneity has a profound impact on the properties of two-dimensional van der Waals materials. This study reveals that the substitution of sulfur on the selenium atomic sites in Fe1-ySe1-xSx causes differences in bond length and strong disorder, suppressing the superconducting transition temperature and enhancing disorder-related scattering. Furthermore, the research finds that the high-temperature metallic resistivity in the presence of strong disorder exceeds the Mott limit, indicating a violation of Matthiessen's rule and the Mooij law.
Article
Chemistry, Physical
Subhasish Mandal, Kristjan Haule, Karin M. Rabe, David Vanderbilt
Summary: Systematic investigation using first principles calculations reveals that the computed bandwidths of nearly free-electron metals can be well described by the local approximation to the self-energy, providing a good agreement with angle-resolved photoemission experiments.
NPJ COMPUTATIONAL MATERIALS
(2022)
Correction
Multidisciplinary Sciences
Xiaoyu Deng, Katharina M. M. Stadler, Kristjan Haule, Seung-Sup B. Lee, Andreas Weichselbaum, Jan von Delft, Gabriel Kotliar
NATURE COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Muntaser Naamneh, Eduardo B. B. Guedes, Abhinav Prakash, Henrique M. M. Cardoso, Ming Shi, Nicholas C. C. Plumb, Walber H. H. Brito, Bharat Jalan, Milan Radovic
Summary: Materials that combine physically incompatible properties can lead to devices with novel functionalities. This study focuses on doped perovskite alkaline earth stannates BaSnO3, which exhibit both high light transparency and high electrical conductivity. The research reveals the existence of a 2-dimensional metallic state at the SnO2-terminated surface of 1% La-doped BaSnO3 thin films, making them suitable for engineering highly conductive transition metal oxide heterostructures.
COMMUNICATIONS PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Hang Li, Walber H. Brito, Eduardo B. Guedes, Alla Chikina, Rasmus T. Dahm, Dennis V. Christensen, Shinhee Yun, Francesco M. Chiabrera, Nicholas C. Plumb, Ming Shi, Nini Pryds, Milan Radovic
Summary: Relatively simple surface preparation can reconstruct the 2D electron gas (2DEG) at the SrTiO3 surface, leading to a Lifshitz-like transition. Experimental methods combined with ab initio calculations reveal that the modulation of the surface band structures can be achieved via transforming the chemical composition at the atomic scale. Additionally, ARPES experiments demonstrate that vacuum ultraviolet light can effectively alter the band renormalization of the 2DEG system and control the electron-phonon interaction.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Victor Rosendal, Walber H. Brito, Milan Radovic, Alla Chikina, Mads Brandbyge, Nini Pryds, Dirch H. Petersen
Summary: This study maps the energy landscape of octahedral tilting in Strontium niobate using density functional theory calculations, and finds that compressive strain induces tilting around the out-of-plane axis, while tensile strain induces tilting around the in-plane axes. The competition between in-phase and out-of-phase tilting in SrNbO3 allows for tuning the thermoelectric and optical properties. The study also shows how the tilt angle and mode affect the Seebeck coefficient and the plasma frequency due to changes in the band structure.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Moallison F. Cavalcante, Rodrigo G. Pereira, Maria C. O. Aguiar
Summary: We investigate the dynamics of the Kondo effect in a system of two metallic Hubbard chains coupled to a magnetic impurity after a quantum quench. For noninteracting electrons, the charge current across the impurity is determined by a scaling function involving the Kondo time. In the case of interacting electrons, we observe a decrease in the Kondo time with increasing repulsive interaction strength, and the time dependence of the current exhibits characteristics of the Kondo effect in a Luttinger liquid. Our findings emphasize the significance of nonequilibrium dynamics in studying quantum impurities in interacting systems.
Article
Materials Science, Multidisciplinary
Isaac M. Carvalho, Helena Braganca, Walber H. Brito, Maria C. O. Aguiar
Summary: This study investigates the formation of charge and spin ordering starting from a noninteracting state under finite electronic interactions. Using time-dependent density matrix renormalization group, the researchers analyze linear finite-time quenches in on-site and nearest-neighbor interactions, identifying impulse, intermediate, and adiabatic regimes of time evolution. The findings show that the adiabatic regime is reached with distinct ramping timescales depending on whether charge density wave (CDW) or spin density wave (SDW) is formed, with interesting observations in the intermediate regime.
Article
Materials Science, Multidisciplinary
P. H. Souza, D. P. de Andrade Deus, W. H. Brito, R. H. Miwa
Summary: We studied the effects of graphene on the electronic and magnetic properties of α-RuCl3 and OsCl3 monolayers using first-principles calculations. Our findings suggest that the electronic and magnetic properties of TM trichloride monolayers can be controlled by graphene and external electric fields.
Article
Materials Science, Multidisciplinary
Helena Braganca, M. F. Cavalcante, R. G. Pereira, Maria C. O. Aguiar
Summary: We investigate a quantum quench where a magnetic impurity is suddenly connected to Hubbard chains described by Tomonaga-Luttinger liquid theory. By using tDMRG technique, we examine how the charge, spin, and entanglement propagate in the chains after the quench, and link light-cone velocities to holons and spinons dispersion. The study reveals that increasing interaction in the chains leads to faster decay of local magnetization at the impurity site, despite a decrease in spin velocity. The analytical expression derived for impurity magnetization relaxation aligns well with tDMRG results at intermediate timescales, offering valuable insights into the time evolution of Kondo screening cloud in interacting systems.
