Article
Optics
D. G. Suarez-Forero, D. W. Session, M. Jalali Mehrabad, P. Knuppel, S. Faelt, W. Wegscheider, M. Hafezi
Summary: The interplay between time-reversal symmetry breaking and strong light-matter coupling in two-dimensional gases brings intriguing aspects to polariton physics. This combination can lead to a polarization/spin-selective light-matter interaction in the strong coupling regime. We demonstrate circular-polarization dependence of the vacuum Rabi splitting by coupling a 2D gas in the quantum Hall regime to a microcavity, providing a quantitative understanding of the phenomenon.
Article
Optics
Haonan Ling, Arnab Manna, Jialiang Shen, Ho-Ting Tung, David Sharp, Johannes Froch, Siyuan Dai, Arka Majumdar, Artur R. Davoyan
Summary: This study investigates the interaction between light and matter in van der Waals MoS2 nanophotonic devices and demonstrates deep subwavelength optical field confinement in nanostructures, which has the potential to significantly reduce the size of integrated photonic devices and opto-electronic circuits.
Review
Nanoscience & Nanotechnology
Yoon-Min Lee, Seong-Eun Kim, Jeong-Eun Park
Summary: The study of strong coupling between light and matter has gained significant attention in recent years due to its potential applications in diverse fields. Plasmonic cavities, particularly colloidal metal nanoparticles, offer an attractive alternative for ultracompact polaritonic systems at room temperature. This review highlights the advantages of colloidal metal nanoparticles as plasmonic cavities, focusing on their facile synthesis, tunable plasmonic properties, and easy integration with excitonic materials. The review explores recent examples of strong coupling in single nanoparticles, dimers, nanoparticle-on-a-mirror configurations, and other types of nanoparticle-based resonators, revealing their potential in nanophotonic applications.
Article
Chemistry, Multidisciplinary
Ivan S. Sokolov, Dmitry V. Averyanov, Oleg E. Parfenov, Alexander N. Taldenkov, Maxim G. Rybin, Andrey M. Tokmachev, Vyacheslav G. Storchak
Summary: Imprinting magnetism into graphene may lead to unconventional electron states and enable the design of spin logic devices with low power consumption. The ongoing active development of 2D magnets suggests their coupling with graphene to induce spin-dependent properties via proximity effects. In particular, the recent discovery of submonolayer 2D magnets on surfaces of industrial semiconductors provides an opportunity to magnetize graphene coupled with silicon.
Article
Optics
Rashmi Kumari, Anjali Yadav, Shubhanshi Sharma, Tapajyoti Das Gupta, Shailendra Kumar Varshney, Basudev Lahiri
Summary: Van der Waals optical metasurfaces consisting of graphene and hBN are used for biosensing in the mid-infrared region, achieving high sensitivity detection of organic analytes through surface-enhanced infrared absorption based on phonon polaritons.
Article
Chemistry, Physical
Haixia Xu, Mingli Yang, Yihang Chen
Summary: In this study, a strong coupling system consisting of a polar dielectric GaAs nanolayer and a graphene sheet is proposed. Both the epsilon-near-zero (ENZ) mode and graphene plasmon (GP) mode can be excited in this system and strongly couple with each other. The hybridized ENZ-GP modes exhibit long propagation length and strong optical field confinement.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Seongheon Kim, Byung Hoon Woo, Soo-Chan An, Yeonsoo Lim, In Cheol Seo, Dai-Sik Kim, SeokJae Yoo, Q-Han Park, Young Chul Jun
Summary: By exploiting momentum space topology, topological control of 2D perovskite emission in the strong coupling regime via polaritonic bound states in the continuum (BICs) is demonstrated, with observation of polarization singularities and achieving high degree of circular polarization in symmetry-broken structures. Lower polariton modes shifting to low-loss spectral region in strong coupling regime results in strong emission enhancement and large degree of circular polarization.
Article
Physics, Applied
Nikos Iliopoulos, Ioannis Thanopulos, Vasilios Karanikolas, Emmanuel Paspalakis
Summary: We investigate the entanglement dynamics between two qubits and a graphene nanodisk using the macroscopic quantum electrodynamics method. Our findings show that as the free-space decay rate increases, the decaying Rabi oscillations in the qubit population dynamics change to complex non-Markovian dynamical population evolution. This is also reflected in the concurrence, which can reach values up to 0.5 under weak or moderate light-matter coupling conditions and transiently higher values under stronger coupling conditions. These results demonstrate the potential of graphene nanostructures for realizing high degrees of entanglement at the nanoscale, which is crucial for quantum technology applications.
APPLIED PHYSICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Xiaofei Xiao, Stefan A. Maier, Vincenzo Giannini
Summary: The proposed imaging-based nanophotonic technique uses deep subwavelength graphene plasmon nanocavities to determine the refractive index of analytes, allowing for retrieval of molecular concentration. This method features a two-dimensional array of suspended graphene plasmon nanocavities with high field enhancement, compression of graphene plasmons, and spatial absorption pattern readout for refractive index measurement.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Theis P. P. Rasmussen, A. Rodriguez Echarri, F. Javier Garcia de Abajo, Joel D. D. Cox
Summary: The subwavelength plasmonic near-field enhancement is hindered by large ohmic losses in good plasmonic materials, while conventional phase-matching of fields in bulk nonlinear crystals is not suitable for realizing nonlinear optical phenomena on the nanoscale. In contrast, highly-doped graphene supports long-lived, highly-confined, and actively-tunable plasmons, making it an excellent platform for both plasmonics and nonlinear optics. By interfacing multiple graphene nanostructures in close proximity, we can trigger nonlocal effects associated with large gradients in the electromagnetic near field to enhance nonlinear response.
Article
Multidisciplinary Sciences
Tetsuya Kambe, Shotaro Imaoka, Misa Shimizu, Reina Hosono, Dongwan Yan, Hinayo Taya, Masahiro Katakura, Hirona Nakamura, Shoichi Kubo, Atsushi Shishido, Kimihisa Yamamoto
Summary: Researchers have discovered a borophene analogue in liquid state, which has an ordered layer structure and exhibits thermal stability and optical switching behavior at high temperatures and low voltages.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Clara Bujalance, Victoria Esteso, Laura Calio, Giulia Lavarda, Tomas Torres, Johannes Feist, Francisco Jose Garcia-Vidal, Giovanni Bottari, Hernan Miguez
Summary: Organic polaritonic solar cells utilize the hybridization of sunlight absorbers and resonator photon modes through strong coupling to control and enhance performance of the devices. Rational design of the layered structure is crucial for optimizing both spectral and angular response of sunlight harvester dyes in ultrastrong coupling regime.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Irati Alonso Calafell, Lee A. Rozema, David Alcaraz Iranzo, Alessandro Trenti, Philipp K. Jenke, Joel D. Cox, Avinash Kumar, Hlib Bieliaiev, Sebastien Nanot, Cheng Peng, Dmitri K. Efetov, Jin-Yong Hong, Jing Kong, Dirk R. Englund, F. Javier Garcia de Abajo, Frank H. L. Koppens, Philip Walther
Summary: Graphene-insulator-metal heterostructures exhibit significantly enhanced optical nonlinearity, offering potential for optically controlled and electrically tunable nano-optoelectronic devices.
NATURE NANOTECHNOLOGY
(2021)
Article
Chemistry, Physical
Yan Zhang, Wenhuan Zhu
Summary: The metal-grating assisted graphene plasmonic asymmetric system offers multiple high-quality near-unity absorption properties, enabling various functions and precise frequency tuning. It also demonstrates outstanding performance in optical sensing, with high sensitivity and FOM factor.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Peng Xie, Qi Ding, Zhengchen Liang, Shiyu Shen, Ling Yue, Hong Zhang, Wei Wang
Summary: This article reports a microcavity-assisted technique for enhancing self-hybridization of excitons and quasibound states in transition metal dichalcogenides (TMDs). Simulation results show that the coupling strength of self-hybridization can be dramatically enhanced using this technique. This approach holds promise for the design of tunable exciton-polariton photonic devices.
Article
Chemistry, Multidisciplinary
Michael Yannai, Raphael Dahan, Alexey Gorlach, Yuval Adiv, Kangpeng Wang, Ivan Madan, Simone Gargiulo, Francesco Barantani, Eduardo J. C. Dias, Giovanni Maria Vanacore, Nicholas Rivera, Fabrizio Carbone, F. Javier Garcia de Abajo, Ido Kaminer
Summary: The ultrafast dynamics of charge carriers in solids is crucial for emerging optoelectronics, photonics, energy harvesting, and quantum technology applications. However, investigating and visualizing such nonequilibrium phenomena at nanometer-femtosecond scales has been a longstanding challenge. In this study, we propose and demonstrate a new interaction mechanism called charge dynamics electron microscopy (CDEM), which enables nanoscale imaging of the femtosecond dynamics of charge carriers in solids. By exploiting the strong interaction of free-electron pulses with terahertz (THz) near fields created by moving charges, we can directly retrieve the THz near-field amplitude and phase, reconstruct movies of the generated charges, and investigate previously inaccessible spatiotemporal regimes of charge dynamics in solids.
Article
Chemistry, Multidisciplinary
Ivan Madan, Eduardo J. C. Dias, Simone Gargiulo, Francesco Barantani, Michael Yannai, Gabriele Berruto, Thomas LaGrange, Luca Piazza, Tom T. A. Lummen, Raphael Dahan, Ido Kaminer, Giovanni Maria Vanacore, F. Javier Garcia de Abajo, Fabrizio Carbone
Summary: Understanding and actively controlling the dynamics of nonequilibrium electron clouds is crucial for various applications. However, these clouds evolve in a complex manner on small scales, making them difficult to study. In this study, we use an ultrafast transmission electron microscope to solve the challenge of characterizing the evolution of electron clouds generated on metallic structures, providing insights into their intricate mechanisms and dynamics. This technique, known as charge dynamics electron microscopy (CDEM), opens up possibilities for studying a wide range of nonequilibrium electrodynamic phenomena on the nanoscale.
Article
Nanoscience & Nanotechnology
Xiangdong Guo, Ning Li, Xiaoxia Yang, Ruishi Qi, Chenchen Wu, Ruochen Shi, Yuehui Li, Yang Huang, F. Javier Garcia de Abajo, En-Ge Wang, Peng Gao, Qing Dai
Summary: Light confinement in nanostructures allows for enhanced light-matter interaction, leading to a wide range of applications. Hexagonal BN nanotubes act as smooth nanocavities that can sustain whispering-gallery modes, with low scattering losses. These nanotubes could potentially enable compact photonic devices with ultrastrong light-matter interactions.
NATURE NANOTECHNOLOGY
(2023)
Article
Physics, Multidisciplinary
F. Javier Garcia de Abajo, Claus Ropers
Summary: The modulation of free electrons with light has been found to be effective in producing attosecond electron wave packets. However, existing research mainly focuses on manipulating the longitudinal wave function component, with limited attention given to the transverse degrees of freedom for temporal shaping. In this study, by utilizing parallel light-electron interactions in separate zones, we demonstrate the simultaneous spatial and temporal compression of a convergent electron wave function, resulting in the formation of sub-angstrom focal spots of attosecond duration. This approach opens up new possibilities for exploring ultrafast atomic-scale phenomena, particularly in attosecond scanning transmission electron microscopy.
PHYSICAL REVIEW LETTERS
(2023)
Article
Multidisciplinary Sciences
Hai Hu, Na Chen, Hanchao Teng, Renwen Yu, Mengfei Xue, Ke Chen, Yuchuan Xiao, Yunpeng Qu, Debo Hu, Jianing Chen, Zhipei Sun, Peining Li, F. Javier Garcia de Abajo, Qing Dai
Summary: Negative refraction is achieved using hybrid topological polaritons in van der Waals heterostructures, allowing for gate-tunable manipulation of mid-infrared radiation. Wide-angle negatively refracted polaritons are observed in partially decorated a-MoO3 films with graphene, demonstrating reversible nanoscale focusing. This technique offers possibilities for electrically tunable super-resolution imaging, nanoscale thermal manipulation, enhanced molecular sensing, and on-chip optical circuitry.
Article
Optics
Xihang Shi, Yaniv Kurman, Michael Shentcis, Liang Jie Wong, F. Javier Garcia de Abajo, Ido Kaminer
Summary: The science and technology of X-ray optics have made significant progress, allowing for the focusing of X-rays in various applications. However, certain forms of tailoring waves that are common in the optical regime have been challenging to achieve in the X-ray regime. We propose a novel concept of X-ray focusing by inducing a curved wavefront during the X-ray generation process, enabling the creation of nanobeams with precise focal spots. This concept bypasses the limitations of traditional X-ray optical components and allows for tunable parameters of the focused hotspot.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Izzah Machfuudzoh, Tatsuki Hinamoto, F. Javier Garcia de Abajo, Hiroshi Sugimoto, Minoru Fujii, Takumi Sannomiya
Summary: This study fills the research gap in direct imaging of optical modes by demonstrating nanoscale optical-field visualization of self-interference of light extracted from excited modes through experimentally obtained photon maps that directly portray the field distributions of the excited eigenmodes. By selectively choosing specific modes using cathodoluminescence-based scanning transmission electron microscopy with angle-, polarization-, and wavelength-resolved capabilities, the internal field distributions of the whispering-gallery modes reveal the interference between multiple modes and the resulting complex patterns dependent on the detection angle and polarization. The direct visualization of internal fields enables a comprehensive understanding of WGMs and can provide insights for the design of nanophotonic applications.
Article
Nanoscience & Nanotechnology
Andrea Konecna, Enzo Rotunno, Vincenzo Grillo, F. Javier Garcia de Abajo, Giovanni Maria Vanacore
Summary: Single-pixel imaging was developed as a technique for probing with light wavelengths undetectable by conventional multi-pixel detectors. However, the spatial resolution of optics-based single-pixel microscopy is limited to hundreds of nanometers due to diffraction. In this study, we propose using optically modulated electrons in ultrafast electron microscopes to achieve subnanometer spatially and temporally resolved single-pixel imaging. Simulation results show that realistic imperfect illumination patterns can be used to reconstruct the sample image and its temporal evolution. Electron single-pixel imaging holds great potential for low-dose probing of beam-sensitive biological and molecular samples, particularly in rapid screening during in situ experiments.
Article
Nanoscience & Nanotechnology
Alvaro Rodriguez Echarri, Fadil Iyikanat, Sergejs Boroviks, N. Asger Mortensen, Joel D. Cox, F. Javier Garcia de Abajo
Summary: The promising applications of photonics rely on the fabrication of high-quality metal thin films with controlled thickness in the range of a few nanometers. These materials exhibit highly nonlinear response to optical fields due to ultrafast electron dynamics. However, the understanding of this phenomenon on such small length scales is limited. In this study, a new mechanism controlling the nonlinear optical response of thin metallic films is revealed, which is dominated by ultrafast electronic heat transport when the film thickness is sufficiently small. By experimentally and theoretically studying electronic transport in these materials, the researchers explained the observed temporal evolution of photoluminescence in two-pulse correlation measurements. They found that ultrafast thermal dynamics plays a crucial role in determining the strength and time-dependent characteristics of the nonlinear photoluminescence signal. Their findings provide new insights into the nonlinear optical response of nanoscale materials and offer possibilities for controlling and utilizing hot carrier distributions in metallic films.
Article
Chemistry, Physical
Lujun Wang, Sotirios Papadopoulos, Fadil Iyikanat, Jian Zhang, Jing Huang, Takashi Taniguchi, Kenji Watanabe, Michel Calame, Mickael L. Perrin, F. Javier Garcia de Abajo, Lukas Novotny
Summary: The authors demonstrate exciton-assisted resonant electron tunnelling in van der Waals heterostructure tunnel junctions. They reveal tunnelling mechanisms involving indirect or direct excitons and optical emission driven by inelastic electron tunnelling. The study highlights the importance of materials with well-defined interfaces and the potential for van der Waals material-based optoelectronic devices.
Article
Multidisciplinary Sciences
John H. Gaida, Hugo Lourenco-Martins, Sergey V. Yalunin, Armin Feist, Murat Sivis, Thorsten Hohage, F. Javier Garcia de Abajo, Claus Ropers
Summary: The paper introduces Lorentz-PINEM for full-field, non-invasive imaging of complex optical near fields at high spatial resolution. The authors use energy-filtered defocus phase-contrast imaging and iterative phase retrieval to reconstruct the phase distribution of interfering surface-bound modes on a plasmonic nanotip. Their approach is applicable for retrieving the spatially varying phase of nanoscale fields and topological modes.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Yves Auad, Eduardo J. C. Dias, Marcel Tence, Jean-Denis Blazit, Xiaoyan Li, Luiz Fernando Zagonel, Odile Stephan, Luiz H. G. Tizei, F. Javier Garcia de Abajo, Mathieu Kociak
Summary: The authors propose a technique that combines free-space light and electron beams to achieve unmatched spatial and spectral resolution. This approach allows detailed investigation of photonic structures, promising advancements in microscopy and quantum optics.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Alejandro Manjavacas, F. Javier Garcia de Abajo
Summary: Single-photon emitters are essential for quantum technologies, but generating single photons along specific directions usually requires complex configurations. In this study, we propose a photon source that can efficiently generate single photons along guided modes. By placing a quantum emitter in a periodically patterned linear waveguide, the emission of photons is preferentially directed along the waveguide in a region close to the period, resulting in a significant reduction in temporal uncertainty. Our research opens up a new approach for producing highly directional single photons with reduced temporal uncertainty.
Article
Chemistry, Multidisciplinary
P. A. D. Goncalves, F. Javier Garcia de Abajo
Summary: This study theoretically demonstrates that core-level photoemission from nanostructures can exhibit spectrally narrow plasmonic features with relatively high probabilities analogous to the direct peak. The morphology and dimensionality of the nanostructures have a dramatic effect on the plasmon-satellite probabilities, and universal scaling laws are found. Additionally, a pump-probe scheme is introduced to explore the ultrafast dynamics of the sampled nanostructure by optically exciting plasmons prior to photoemission.
Article
Chemistry, Multidisciplinary
Eduardo J. C. Dias, Ivan Madan, Simone Gargiulo, Francesco Barantani, Michael Yannai, Giovanni Maria Vanacore, Ido Kaminer, Fabrizio Carbone, F. Javier Garcia de Abajo
Summary: We develop a comprehensive microscopic theory to predict the spatiotemporal dynamics of laser-pulse-induced plasmas, and study the characteristics of terahertz fields generated through electron emission, metal screening, and plasma cloud interactions. We also investigate the interaction with femtosecond electron beams and explain recent ultrafast electron microscopy experiments. Our work contributes fundamental insight into the generation and dynamics of micron-scale electron plasmas and their interaction with ultrafast electron pulses.
NANOSCALE ADVANCES
(2023)