Review
Chemistry, Multidisciplinary
Xiangdong Guo, Wei Lyu, Tinghan Chen, Yang Luo, Chenchen Wu, Bei Yang, Zhipei Sun, F. Javier Garcia de Abajo, Xiaoxia Yang, Qing Dai
Summary: 2D monolayers can be vertically stacked in van der Waals heterostructures to support a wide range of confined polaritons. This offers advantages in terms of controlling the constituent layers, stacking sequence, and twist angles. These heterostructures have extended the performance and functions of polaritons, and potential applications include nanophotonic integrated circuits.
ADVANCED MATERIALS
(2023)
Review
Nanoscience & Nanotechnology
Sergey G. Menabde, Jacob T. Heiden, Joel D. Cox, N. Asger Mortensen, Min Seok Jang
Summary: Polaritonic modes in low-dimensional materials enable strong light-matter interactions and the manipulation of light on nanometer length scales. The recent interest in image polaritons in van der Waals crystals has gained considerable attention in nanophotonics, where a polaritonic material couples with its mirror image in close proximity to a highly conductive metal. These image modes provide an appealing nanophotonic platform with lower propagation loss and access to the nonlocal regime of light-matter interaction.
Article
Chemistry, Multidisciplinary
Wuchao Huang, Fengsheng Sun, Zebo Zheng, Thomas G. Folland, Xuexian Chen, Huizhen Liao, Ningsheng Xu, Joshua D. Caldwell, Huanjun Chen, Shaozhi Deng
Summary: Patterned microstructures on vdW crystals can enhance and tailor the interference effects of phonon polaritons, enabling the tuning of infrared electromagnetic field localizations and providing an effective rationale for engineering infrared light flow in planar photonic devices.
Article
Materials Science, Multidisciplinary
Jiawei Huang, Lei Tao, Ningning Dong, Hongqiang Wang, Song Zhou, Jun Wang, Xiaoyue He, Kehui Wu
Summary: This study explores the launching and propagating properties of HPhPs in α-MoO3 along orthogonal crystal orientations using a holey silicon nitride microcavity, providing abundant possibilities for applications and operations in nanophotonics.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Patricia Aguilar-Merino, Gonzalo Alvarez-Perez, Javier Taboada-Gutierrez, Jiahua Duan, Ivan Prieto, Luis Manuel Alvarez-Prado, Alexey Y. Nikitin, Javier Martin-Sanchez, Pablo Alonso-Gonzalez
Summary: Layered materials bonded by weak van der Waals forces have attracted significant attention in nano-optics due to their ability to support phonon polaritons with strong electromagnetic confinement. Using near-field microscopy, researchers were able to accurately extract the permittivity of alpha-MoO3 and sense its local dielectric environment, silica, demonstrating the versatility of phonon polaritons nanoimaging for characterizing local optical properties of dielectric substrates.
Article
Chemistry, Multidisciplinary
Thales V. A. G. de Oliveira, Tobias Noerenberg, Gonzalo Alvarez-Perez, Lukas Wehmeier, Javier Taboada-Gutierrez, Maximilian Obst, Franz Hempel, Eduardo J. H. Lee, J. Michael Klopf, Ion Errea, Alexey Y. Nikitin, Susanne C. Kehr, Pablo Alonso-Gonzalez, Lukas M. Eng
Summary: Research demonstrates nanoscale-confined phonon polaritons at THz frequencies in vdW semiconductors using scattering-type scanning near-field optical microscopy and a free-electron laser, achieving extreme field confinement and low optical losses.
ADVANCED MATERIALS
(2021)
Article
Multidisciplinary Sciences
A. J. Sternbach, S. H. Chae, S. Latini, A. A. Rikhter, Y. Shao, B. Li, D. Rhodes, B. Kim, P. J. Schuck, X. Xu, X-Y Zhu, R. D. Averitt, J. Hone, M. M. Fogler, A. Rubio, D. N. Basov
Summary: Layered crystals, such as tungsten diselenide, can exhibit unconventional optical properties that allow for the propagation of subdiffractional waveguide modes with hyperbolic dispersion. This study demonstrates optically induced hyperbolicity in WSe2 and explores the role of quantum transitions of excitons in the observed polaritonic response.
Article
Chemistry, Multidisciplinary
Mohammad Amini, Orlando J. Silveira, Viliam Vano, Jose L. Lado, Adam S. Foster, Peter Liljeroth, Shawulienu Kezilebieke
Summary: 2D ferroelectric materials are promising for electrical control of quantum states, and can influence the quantum states of deposited molecules due to their 2D nature. This study reports electrically controllable molecular states in phthalocyanine molecules adsorbed on monolayer ferroelectric material SnTe. The strain and ferroelectric order in SnTe create a transition between two distinct orbital orders in the adsorbed phthalocyanine molecules. The polarization of the ferroelectric domain can be manipulated electrically, providing a starting point for ferroelectrically switchable molecular orbital ordering and ultimately, electrical control of molecular magnetism.
ADVANCED MATERIALS
(2023)
Article
Multidisciplinary Sciences
Long Zhang, Fengcheng Wu, Shaocong Hou, Zhe Zhang, Yu-Hsun Chou, Kenji Watanabe, Takashi Taniguchi, Stephen R. Forrest, Hui Deng
Summary: Controlling matter-light interactions with cavities is crucial in modern science and technology. By integrating MoSe2-WS2 heterobilayers in a microcavity, cooperative coupling between moire-lattice excitons and microcavity photons has been established, providing versatile control of both matter and light. This moire polariton system combines strong nonlinearity and microscopic-scale tuning of matter excitations, offering a platform to study collective phenomena from tunable arrays of quantum emitters.
Article
Nanoscience & Nanotechnology
Florian Dirnberger, Rezlind Bushati, Biswajit Datta, Ajesh Kumar, Allan H. MacDonald, Edoardo Baldini, Vinod M. Menon
Summary: This study reports the emergence of a type of polaritonic quasiparticle in the van der Waals antiferromagnet NiPS3, which has highly correlated electronic degrees of freedom, through strong coupling with photons. Detailed spectroscopic analysis and microscopic theory provide insights into the origin and interactions of these exotic magnetically coupled excitations.
NATURE NANOTECHNOLOGY
(2022)
Review
Chemistry, Multidisciplinary
Tianping Ying, Tongxu Yu, Yanpeng Qi, Xiaolong Chen, Hideo Hosono
Summary: By breaking traditional alloying strategy restrictions, the high entropy concept has expanded the field of alloy exploitation. This review focuses on the combination of the high entropy concept and van der Waals systems to create a new category of materials called high entropy van der Waals materials (HEX). The design strategy for HEX incorporates the local features of high entropy materials and the holistic degrees of freedom in van der Waals materials, successfully leading to the discovery of various high entropy compounds with desirable physical properties. Additionally, deliberate design of structural units and their stacking configuration in HEX can also enhance catalytic performance.
Article
Materials Science, Multidisciplinary
Sergey G. Menabde, Junghoon Jahng, Sergejs Boroviks, Jongtae Ahn, Jacob T. Heiden, Do Kyung Hwang, Eun Sung Lee, N. Asger Mortensen, Min Seok Jang
Summary: Orthorhombic molybdenum trioxide (alpha-MoO3) is a polaritonic van der Waals crystal with strongly anisotropic mid-infrared phonon-polaritons. The coupling of polariton with its mirror image in an adjacent metal leads to a more confined image mode. This research measures the propagation constant of image phonon-polaritons in alpha-MoO3 using monocrystalline gold flakes as a substrate, demonstrating the long lifetime and propagation length of these polaritons.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Zebo Zheng, Fengsheng Sun, Ningsheng Xu, Wuchao Huang, Xuexian Chen, Yanlin Ke, Runze Zhan, Huanjun Chen, Shaozhi Deng
Summary: This study demonstrates the feasibility of tuning the wavelength and damping rate of hyperbolic phonon polaritons (HPhPs) by varying air gaps in a suspended van der Waals α-MoO3 crystal. Results show contradictory wavelength dependencies for HPhPs in different Reststrahlen bands, with a wider tuning range for HPhPs in the lower band compared to the upper band. Notably, a significant elongation of polariton wavelengths and reduction in damping rates were achieved, opening up new opportunities for tunable nanophotonic applications.
ADVANCED OPTICAL MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
Hui-Lei Hou, Cosimo Anichini, Paolo Samori, Alejandro Criado, Maurizio Prato
Summary: In the past 15 years, 2D materials have revolutionized materials science and become powerful components for high-performance chemical sensors. By forming van der Waals heterostructures (VDWHs), the individual drawbacks of 2D materials can be overcome, leading to superior sensitivities, selectivity, and stability. This review discusses the latest developments in chemical sensors based on VDWHs of 2D materials, including sensing mechanisms and future directions with potential impact in environmental sciences and biomedical applications.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Maurits J. A. Houmes, Samuel Manas-Valero, Alvaro Bermejillo-Seco, Eugenio Coronado, Peter G. Steeneken, Herre S. J. van der Zant
Summary: This article investigates the structural anisotropy of CrPS4 and its relationship with magnetic phase transitions and discovers different mechanical response behavior compared to previously studied van der Waals magnets. The results demonstrate the potential of CrPS4 in the field of low-dimensional magnetism and show the potential of mechanical resonators in studying structural modifications in 2D materials and van der Waals heterostructures.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Roland Yingjie Tay, Hongling Li, Zhi Kai Ng, Siu Hon Tsang, Wei Gao, Edwin Hang Tong Teo
Summary: In this study, a new method was developed to synthesize high-quality porous graphene film by incorporating an in situ reduction-oxidation cycling treatment. The graphene film exhibited a holey surface with interconnected ligaments within its porous interior, resulting in superior in-plane electrical conductivity. Compared to state-of-the-art electromagnetic interference shielding materials, this porous graphene film showed excellent performance with high specific and absolute shielding effectiveness.
ADVANCED MATERIALS INTERFACES
(2022)
Review
Physics, Applied
M. Shrestha, G. K. Lau, A. K. Bastola, Z. Lu, A. Asundi, E. H. T. Teo
Summary: Most modern high-rise buildings use glass facades, but this can result in issues such as compromised visual privacy and energy loss. Optically tunable windows, which can adjust daylighting, heat radiation, and transparency, are seen as a potential solution. However, existing commercial options have limitations, such as high cost and limited performance. Therefore, researchers are exploring low-cost actively tunable windows. However, most of these emerging technologies do not meet all the requirements. To fully understand and improve these technologies, an in-depth review of their optical principles is essential.
APPLIED PHYSICS REVIEWS
(2022)
Article
Chemistry, Multidisciplinary
Shiyong Huang, Zhi Kai Ng, Hongling Li, Apoorva Chaturvedi, Jian Wei Mark Lim, Roland Yingjie Tay, Edwin Hang Tong Teo, Shuyan Xu, Kostya (Ken) Ostrikov, Siu Hon Tsang
Summary: This study demonstrates the excellent stability of hexagonal boron nitride nanosheets (hBNNS) under extreme conditions such as high-energy ions and reactive atomic oxygen. The results highlight the potential of hBNNS films as protective, thermally conductive, and insulating layers in spacecrafts, electric plasma satellite thrusters, and semiconductor optoelectronic devices.
Article
Multidisciplinary Sciences
Yinming Shao, Aaron J. Sternbach, Brian S. Y. Kim, Andrey A. Rikhter, Xinyi Xu, Umberto De Giovannini, Ran Jing, Sang Hoon Chae, Zhiyuan Sun, Seng Huat Lee, Yanglin Zhu, Zhiqiang Mao, James C. Hone, Raquel Queiroz, Andrew J. Millis, P. James Schuck, Angel Rubio, Michael M. Fogler, Dmitri N. Basov
Summary: Metals are effective media for guiding and manipulating light at the nanoscale. In this study, propagating hyperbolic waves were observed in a layered nodal-line semimetal, enabled by the polaritonic hybridization between near-infrared light and nodal-line plasmons.
Article
Chemistry, Multidisciplinary
Xinzhong Chen, Suheng Xu, Sara Shabani, Yueqi Zhao, Matthew Fu, Andrew J. Millis, Michael M. Fogler, Abhay N. Pasupathy, Mengkun Liu, D. N. Basov
Summary: The ability to perform nanometer-scale optical imaging and spectroscopy is crucial for decoding low-energy effects in quantum materials, as well as identifying vibrational fingerprints in planetary and extraterrestrial particles, catalytic substances, and aqueous biological samples. The scattering-type scanning near-field optical microscopy (s-SNOM) technique, along with artificial intelligence (AI) and machine learning (ML) algorithms, can greatly enhance the efficiency, accuracy, and intelligence of scanning probe optical nanoscopy.
ADVANCED MATERIALS
(2023)
Article
Physics, Applied
Y. Zhao, X. Chen, Z. Yao, M. K. Liu, M. M. Fogler
Summary: Scanning near-field optical microscopy is an effective technique for nanoscale spectroscopy. However, extracting optical constants from the measured near-field signal is challenging due to complex interaction. We propose a deep learning network combined with a fitting algorithm for automated parameter extraction, which shows superior accuracy, noise stability, and computational speed in simulated spectra.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Multidisciplinary Sciences
A. J. Sternbach, S. L. Moore, A. Rikhter, S. Zhang, R. Jing, Y. Shao, B. S. Y. Kim, S. Xu, S. Liu, J. H. Edgar, A. Rubio, C. Dean, J. Hone, M. M. Fogler, D. N. Basov
Summary: We visualized negative refraction of phonon polaritons, which occur when passing through a planar interface between molybdenum oxide (MoO3) and isotopically pure hexagonal boron nitride (h11BN). The polaritons, hybrids of infrared photons and lattice vibrations, form collimated rays that exhibit negative refraction. These rays can circulate along closed diamond-shaped trajectories at a specific frequency co0. We found that the polariton eigenmodes display regions of both positive and negative dispersion, with multiple gaps resulting from polaritonic-level repulsion and strong coupling.
Review
Engineering, Mechanical
Jueyu Chen, Edwin Hang Tong Teo, Kui Yao
Summary: Haptic technology, which uses actuators to provide tactile feedback for human-computer interaction, is increasingly being applied in electronic devices. This review compares four types of electromechanical actuators: electromagnetic, electrostatic, piezoelectric, and electrostrictive actuators, for achieving haptic feedback. The driving principles, working conditions, applicable scopes, and characteristics of these actuators are fully compared. The design and values of piezoelectric actuators for achieving sophisticated and high-definition haptic effects are particularly emphasized. The current status and future directions of different types of haptic actuators are discussed.
Article
Biotechnology & Applied Microbiology
Milan Shrestha, Leonardus Depari, Maziar Shakerzadeh, Ranjana Shivakumar, Edwin H. T. Teo
Summary: Researchers developed a viscous composite ink with PEDOT:PSS and PDMS for coating on untreated PDMS, allowing for more uniform and adhesive ink-based electrodes. These coatings are transparent, stretchable, electrically conductive, and act as compliant electrodes. They also fabricated transparent dielectric elastomer actuators using PEDOT:PSS/PDMS electrodes, which had slightly lower actuation strain and breakdown fields compared to traditional graphite electrodes, but improved robustness in localized dielectric breakdown events.
SENSORS AND ACTUATORS REPORTS
(2023)
Article
Chemistry, Multidisciplinary
Daniel J. Rizzo, Jin Zhang, Bjarke S. Jessen, Francesco L. Ruta, Matthew Cothrine, Jiaqiang Yan, David G. Mandrus, Stephen E. Nagler, Takashi Taniguchi, Kenji Watanabe, Michael M. Fogler, Abhay N. Pasupathy, Andrew J. Millis, Angel Rubio, James C. Hone, Cory R. Dean, D. N. Basov
Summary: The use of work-function-mediated charge transfer is explored for nanoscale electrostatic control of atomic layers. A thin layer of a-RuCl3 is found to induce emergent nano-optical behavior in hBN through interlayer charge polarization. The propagation length of hBN phonon polaritons is significantly reduced by the interfacial dipole formed by a-RuCl3, and a novel resonance is observed in nano-optical spectroscopy experiments. These findings demonstrate the potential of charge-transfer heterostructures for tailoring optoelectronic properties of 2D insulators.
Article
Nanoscience & Nanotechnology
Michael Dapolito, Makoto Tsuneto, Wenjun Zheng, Lukas Wehmeier, Suheng Xu, Xinzhong Chen, Jiacheng Sun, Zengyi Du, Yinming Shao, Ran Jing, Shuai Zhang, Adrien Bercher, Yinan Dong, Dorri Halbertal, Vibhu Ravindran, Zijian Zhou, Mila Petrovic, Adrian Gozar, G. L. Carr, Qiang Li, Alexey B. Kuzmenko, Michael M. Fogler, D. N. Basov, Xu Du, Mengkun Liu
Summary: Magnetic fields can significantly affect electron motion in quantum materials. We have visualized the magnetic-field-tunable dispersion of propagating magnetoexciton polaritons in near-charge-neutral graphene. By imaging these collective modes and their associated nano-electro-optical responses, we have identified pronounced optical and photo-thermal electric effects at the sample edges, particularly near charge neutrality. Our nano-magneto-optics approach allows us to explore and manipulate magnetopolaritons in specimens with low carrier doping by utilizing high magnetic fields. The dispersion of Dirac magnetoexcitons in charge-neutral graphene has been directly imaged up to 7 T using a magneto cryogenic near-field microscope.
NATURE NANOTECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Hongling Li, Zhi Kai Ng, Roland Yingjie Tay, Shiyong Huang, Siu Hon Tsang, Edwin Hang Tong Teo
Summary: In this study, graphene/MXene composite thin films with excellent flexibility and EMI shielding capability were fabricated. The composite thin films exhibited high EMI shielding effectiveness and superb electrothermal conversion capability, providing a facile method for EMI shielding and thermal management applications in next-generation flexible electronics.
ACS APPLIED NANO MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Ran Jing, Rocco A. Vitalone, Suheng Xu, Chiu Fan Bowen Lo, Zaiyao Fei, Elliott Runburg, Yinming Shao, Xinzhong Chen, Fabian Mooshammer, Alexander S. Mcleod, Mengkun Liu, Michael M. Fogler, David H. Cobden, Xiaodong Xu, D. N. Basov
Summary: In this study, the real-space features of the plasmonic response of few-layer WTe2 were visualized and evaluated using time-domain THz nanoimaging technique combined with scattering amplitude experiments.
Article
Physics, Multidisciplinary
Y. Zhao, M. M. Fogler
Summary: We have developed a deep neural network that can reconstruct the shape of a polygonal domain by using the first hundred Dirichlet Laplacian eigenvalues. The network maps input spectra to a latent space and predicts the discretized image of the domain on a square grid. The predictions are highly accurate for both concave and convex pentagons, indicating that the network has discovered fundamental properties of the Laplacian operator and rotational symmetry.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Physics, Multidisciplinary
Zhiyuan Sun, D. N. Basov, M. M. Fogler
Summary: We analyze nonlinear optics schemes for generating pairs of quantum entangled plasmons in graphene. We predict high pair-generation rates due to the strong optical nonlinearity and field concentration in graphene. The schemes studied include spontaneous parametric down conversion and degenerate four-wave mixing, both of which have potential for measuring position-momentum entanglement through nano-optical experiments.
PHYSICAL REVIEW RESEARCH
(2022)
