Article
Chemistry, Physical
Sasa Harkai, Kaushik Pal, Samo Kralj
Summary: Topological defects, such as disclinations, in liquid crystals are of great interest due to their universal behavior and potential applications. Local melting can trigger the splitting of defects, while nanoparticles can manipulate the core structures. This research provides insights for various fields of physics.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Chemistry, Physical
Cuiling Meng, Jin-Sheng Wu, Ivan I. Smalyukh
Summary: Liquid crystals can robustly steer beams of light with optical axis patterns of singular vortex lines, which can be reconfigured by external stimuli. The periodic arrays of vortices obtained by photo-patterning enable vortex-mediated fission of optical solitons, resulting in lightning-like propagation patterns. Pre-designed patterns and spatial trajectories of vortex lines in high-birefringence liquid crystals can steer light into closed loops or even knots. Liquid crystals with vortex lattices have potential applications in beam steering, telecommunications, virtual reality, and anticounterfeiting, as well as providing a model system for studying light-defect interactions including the light-steering action of cosmic strings.
Article
Chemistry, Physical
Wei Si, Zhendong Zhu, Gensheng Wu, Yin Zhang, Yunfei Chen, Jingjie Sha
Summary: Scientists have proposed an encoding manipulation method to control the movement of a DNA-nanoparticle assembled nanorobot. By controlling the applied electric field and surface charge density of each nanopore, the nanorobot can be captured, released, jumped, and crawled.
Article
Optics
S. E. Skipetrov, P. Wulles
Summary: We study the influence of disorder on topological phenomena in honeycomb lattices of atoms coupled by the electromagnetic field. Disorder can induce transitions between different topological phases and drive the system into a topological Anderson insulator state. The nontrivial topology of the photonic band structure can suppress Anderson localization of disorder-induced modes in the band gap of the ideal lattice. Moreover, disorder can open a topological pseudogap and introduce spatially localized modes in an otherwise topologically trivial system.
Article
Multidisciplinary Sciences
Yequan Xiao, Zeyu Fan, Mamiko Nakabayashi, Qiaoqiao Li, Liujiang Zhou, Qian Wang, Changli Li, Naoya Shibata, Kazunari Domen, Yanbo Li
Summary: This study presents a heterogeneous doping strategy that decouples light absorption and carrier transport in semiconductor thin film photoelectrodes, improving their efficiency for solar-to-hydrogen conversion.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Antonio Ferraro, Pino Cerza, Valentina Mussi, Luca Maiolo, Annalisa Convertino, Roberto Caputo
Summary: The study demonstrates efficient photothermal conversion in disordered silicon nanowires, with fast heat generation and adjustable temperature increase observed in a confined region around the laser spot. This technology, combining enhanced light trapping and nonradiative recombination, is cost-effective, low-temperature, and suitable for applications in various fields.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Physics, Multidisciplinary
Pawel Pieranski, Mehdi Zeghal, Maria Helena Godinho, Patrick Judeinstein, Remi Bouffet-Klein, Bastien Liagre, Nicodeme Rouger
Summary: The concept of topological defects is universally applicable in condensed matter, including helical topological defects, dislocations, and vortices. This study focuses on the generation and behavior of primary tangles in cholesterics. The primary tangles can form double helices individually or combine according to simple algebraic rules.
PHYSICAL REVIEW LETTERS
(2023)
Article
Optics
Hooman Barati Sedeh, Danilo G. Pires, Nitish Chandra, Jiannan Gao, Dmitrii Tsvetkov, Pavel Terekhov, Ivan Kravchenko, Natalia Litchinitser
Summary: Structured lights, such as beams with spin and orbital angular momenta and various polarizations, have attracted interest for their unique properties in optical and quantum communications, micromanipulation, and imaging. Additionally, structured optical materials have opened new opportunities for controlling light flow and sensing. However, the interaction between structured light and complex-shaped materials has not been fully explored.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Physical
Churong Ma, Feng Zhao, Fangrong Zhou, Meng Li, Zhaoqiang Zheng, Jiahao Yan, Jie Li, Xiangping Li, Bai-ou Guan, Kai Chen
Summary: Manipulating light-matter interaction at the nanoscale is essential for many photonic applications. Optical nanoantennas, made of metallic or dielectric materials, have unique optical properties that allow them to couple electromagnetic waves with subwavelength entities. However, fabricating these nanoantennas in a high-throughput and cost-effective manner remains challenging. In this work, a versatile nanofabrication method is presented, capable of producing large-scale optical nanoantennas with different shapes. Both metallic and dielectric nanoantennas can be easily fabricated in a high-throughput fashion. This method shows potential for a wide range of applications.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Physics, Multidisciplinary
Ruben D. Muelas-Hurtado, Karen Volke-Sepulveda, Joao L. Ealo, Franco Nori, Miguel A. Alonso, Konstantin Y. Bliokh, Etienne Brasselet
Summary: The observation of polarization singularities, topological Mobius-strip structures, and skyrmionic textures in 3D polarization fields of inhomogeneous sound waves opens up new possibilities for the investigation and applications of topological features and nontrivial 3D vector properties of structured sound waves.
PHYSICAL REVIEW LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Richard Stephen Winkler, Yangyang Zhang, Qi Zhang, Zhe Wang, Yimei Zhu, Myung-Geun Han, Darrell G. Schlom, Nagarajan Valanoor
Summary: The combination of topological defect mobility and exploitation of boundary conditions in bilayer heterostructures has led to an approximate 45% increase in effective d(33) response compared to a single layer on silicon, demonstrating the potential for enhanced actuation responses. The bilayer structure also exhibits large-scale polarization switching on a silicon substrate.
ADVANCED ELECTRONIC MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Takumi Sato, Katsuaki Sugawara, Takemi Kato, Yuki Nakata, Seigo Souma, Kunihiko Yamauchi, Tamio Oguchi, Takashi Takahashi, Takafumi Sato
Summary: By fabricating TI/TI heterostructures, a method free from introducing crystal impurities through chemical substitution can be implemented, and the evolution of band structures can be observed by angle-resolved photoemission spectroscopy, thus manipulating Dirac fermions in TIs.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Physical
N. N. Kurus, I. A. Milekhin, N. A. Nebogatikova, I. Antonova, E. E. Rodyakina, A. G. Milekhin, A. Latyshev, D. R. T. Zahn
Summary: This study focuses on enhancing Raman scattering in multilayered graphene films through plasmonic interaction. By placing the films on a plasmonic substrate consisting of arrays of gold nanodisks, resonant Raman enhancement of the main vibrational modes of multilayered graphene was achieved. The results showed a 25-fold enhancement for nanodisks with a diameter of 103 nm. Moreover, stronger local enhancement (50-fold) was obtained using gap-mode tip-enhanced Raman scattering. The study also revealed the presence of nanofolds in the graphene film, which exhibited mechanical stresses up to 0.7% and lower frequency positions for certain vibrational modes.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Multidisciplinary Sciences
Alex Dikopoltsev, Tristan H. Harder, Eran Lustig, Oleg A. Egorov, Johannes Beierlein, Adriana Wolf, Yaakov Lumer, Monika Emmerling, Christian Schneider, Sven Hoefling, Mordechai Segev, Sebastian Klembt
Summary: Topological insulator lasers are semiconductor laser arrays that utilize topology to create a single coherent laser from multiple emitters. The vertical-cavity surface-emitting laser (VCSEL) array demonstrated in this study emits at a single frequency and displays interference, showcasing the mutual coherence of the emitters. This experiment highlights the power of topological transport of light, where even with most of the light oscillating vertically, the small in-plane coupling forces individual emitters to behave as a single laser.
Article
Multidisciplinary Sciences
Ki Young Lee, Seungjin Yoon, Seok Ho Song, Jae Woong Yoon
Summary: This paper proposes a topological beam emitter structure with submicrometer footprint size, small divergence angle, high efficiency, and adaptable beam shaping capability, making it suitable for various applications.
Article
Chemistry, Physical
Nicola Pellizzi, Alfredo Mazzulla, Pasquale Pagliusi, Gabriella Cipparrone
Summary: Core-shell architecture allows for customization of microparticles by selecting the composition and aggregation state of the inner and outer materials. Gold nanoparticles coating can modify the optical properties of chiral microparticles and improve the stability of microlasers.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Yuzhi Shi, Lei-Ming Zhou, Ai Qun Liu, Manuel Nieto-Vesperinas, Tongtong Zhu, Amir Hassanfiroozi, Jingquan Liu, Hui Zhang, Din Ping Tsai, Hang Li, Weiqiang Ding, Weiming Zhu, Ye Feng Yu, Alfredo Mazzulla, Gabriella Cipparrone, Pin Chieh Wu, C. T. Chan, Cheng-Wei Qiu
Summary: This study reveals the emergence of superhybrid modes with magnetic multipoles and electric toroidal moments, excited by linearly polarized beams, leading to giant positive and negative optical torques on Mie-resonant particles. These giant and reversed torques are observed for the first time in the scattering spectrum, opening up a new avenue for exploring metaoptics and optical manipulations.
Article
Materials Science, Multidisciplinary
Tiziana Ritacco, Dante M. Aceti, Gianfranco De Domenico, Michele Giocondo, Alfredo Mazzulla, Gabriella Cipparrone, Pasquale Pagliusi
Summary: Cholesteric liquid crystals with self-organized helical arrangement allow for tuning the structure to achieve custom optical properties, demonstrated by polymeric microstructures with tailored photonic band gaps.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Physical
Ivan Yakovkin, Andrii Lesiuk, Mykhailo Ledney, Victor Reshetnyak
Summary: The orientational instability of a director in a planar flexoelectric nematic liquid crystal cell in a constant electric field perpendicular to the cell substrates is investigated. The influence of the initial surface orientation, liquid crystal, and electric field on the orientation of the easy axis on one of the polymer substrates is studied. The reorientation of the elastic parts of the polymer molecules of the substrate is due to the interaction of intrinsic or induced dipole moments with the electric field. The effect of the electric field on the surface free energy of the nematic is considered to be linear or quadratic. The temporal behavior of the director after voltage application and its return to the initial homogeneous state after switching off the voltage are studied. The characteristic turn-on/off times and the time of reaching the stationary state are calculated and their dependence on the system parameters is investigated. The transmittance of the nematic liquid crystal cell for normally incident light is also calculated.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Materials Science, Multidisciplinary
O. Sova, T. J. Sluckin, S. Kaur, H. F. Gleeson, V. Reshetnyak
Summary: This paper constructs a theoretical model for the electronic liquid crystal contact lens for the correction of presbyopia. The study shows good agreement between theory and experimental data, although the precise parameters of the lens differ slightly from the original design. The model is useful for engineering optimization of the existing prototype.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Materials Science, Multidisciplinary
Biagio Audia, Pasquale Pagliusi, Alfredo Mazzulla, Gabriella Cipparrone
Summary: The increasing demand for ultracompact micro- and nano-optics in augmented/virtual reality, displays, and Fourier optics is hindered by inefficient and non-tunable meta-solutions as well as complex fabrication methods. This study introduces a broadband laser composed of closely correlated lines that enables the simultaneous encoding of multiplexed, independent, and cross-talk free holograms with nanometric separation through interference patterning. The findings demonstrate the potential of this unconventional light source in overcoming spatial resolution limitations and providing reconfigurable structured optics with advantages including scalability, ease of use, cost-effectiveness, and reduced time and energy consumption.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Crystallography
Svitlana P. Bielykh, Liana Lucchetti, Victor Yu. Reshetnyak
Summary: We proposed a theoretical model of a cylindrical tunable liquid crystal lens based on the modulation of anchoring energy. The model describes the dependence of the focal length on the applied voltage and presents a theoretical study of the lens aberrations. The results obtained are of general relevance and can be used to optimize the performances of every type of liquid crystal lens with a parabolic profile.
Article
Optics
Ivan Yakovkin, Victor Reshetnyak
Summary: This study investigates the tunability of plasmonic resonances in gold and silver nanosphere arrays embedded in a liquid crystal matrix. The results show that the optical properties of these arrays can be modulated by reorienting the liquid crystal, leading to a shift in the plasmonic resonance wavelength. Both gold and silver nanosphere arrays exhibit notable near-field amplification.
Article
Materials Science, Multidisciplinary
Kyung Min Lee, Victor Yu. Reshetnyak, Cedric P. P. Ambulo, Zachary M. M. Marsh, Michael E. E. McConney, Nicholas P. P. Godman
Summary: This study introduces a novel anti-counterfeiting material, holographic polymer stabilized liquid crystal gels (H-PSLC gels), which can switch optical colors and patterns under electric current. The optical properties of H-PSLC gels can be controlled by adjusting the magnitude and direction of the electric current.
MATERIALS ADVANCES
(2023)
Article
Chemistry, Multidisciplinary
V. Yu. Reshetnyak, I. P. Pinkevych, N. P. Godman, T. J. Bunning, D. R. Evans
Summary: The reflection spectrum of a hybrid structure, consisting of a metal film and a holographic grating made of polymer and liquid crystal layers, is investigated. An optical Tamm state (OTS) is formed in the region of the grating band gap, resulting in a narrow dip in the reflection spectrum. The parameters of the polymer and liquid crystal determine the spectral position of the dip, while the type and thickness of the metal affect its magnitude.
Article
Physics, Fluids & Plasmas
V. Yu. Reshetnyak, I. P. Pinkevych, T. J. Bunning, M. E. McConney, D. R. Evans
Summary: Theoretical study is conducted on the reflection spectrum of linearly polarized light by a system composed of a metal film and two adjacent cholesteric liquid crystals (CLCs) with opposite helical twists. The system includes a dielectric index-matching layer (DIML) between the metal film and the CLC layers. It is found that optical Tamm states (OTSs) can be excited by linearly polarized light in such a system. The influence of CLC pitch, refractive indices, and thicknesses of DIML and metal film on the manifestation of OTSs in the reflection spectrum is examined, and the strong influence of DIML thickness on OTS wavelength and the appearance of multiple OTSs with increasing DIML thickness are observed.
Article
Physics, Fluids & Plasmas
A. I. Lesiuk, M. F. Ledney, V. Yu. Reshetnyak
Summary: The paper presents a theoretical description of light-induced nematic liquid crystal reorientation in a cell with gold nanoparticles deposited on one of the bounding substrates. The study shows that the surface plasmon resonance in the nanoparticles significantly affects the threshold of director reorientation. A mathematical model of surface free-energy density is given, considering the influence of the local electric field on the near-surface nematic layer at the substrate with gold nanoparticles. The calculated threshold intensity of director orientation instability and its dependence on the wavelength of incident light and the degree of filling of the surface with gold nanoparticles are analysed. The comparison of theoretical calculations with experimental data confirms the full adequacy of the proposed theoretical model.
Article
Engineering, Electrical & Electronic
Tiziana Ritacco, Pasquale Pagliusi, Michele Giocondo
Summary: This study successfully demonstrates the patterning of gold nanoparticles using Multi-Photon Direct Laser Writing in wet polymeric matrices. The role of the polymeric matrix, the interaction between nanoparticles and the surrounding materials, as well as the influence of temperature on particle distribution and size are thoroughly analyzed. A protocol for patterning gold nanoparticles without the use of polymer is also illustrated.
IEEE TRANSACTIONS ON NANOTECHNOLOGY
(2022)
