Article
Optics
Jiamin Liu, Wenqi Gong, Lei Li, Song Zhang, Jinlong Zhu, Rong Chen, Hao Jiang, Shiyuan Liu
Summary: This paper presents an in-situ characterization method based on Mueller-matrix ellipsometry for investigating the longitudinal MO Kerr effects occurring in subwavelength thick ferromagnetic films. The proposed method allows reliable capture of the weak MO Kerr response signal of the ferromagnetic films with high repeatability precision better than 0.0002.
OPTICS AND LASERS IN ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Jing Chen, Guohua Wu, Ping Gu, Yumei Tang, Chun Yang, Zhendong Yan, Chaojun Tang, Zhengqi Liu, Fan Gao, Pinggen Cai
Summary: The study focuses on enhancing the transverse magneto-optical Kerr effect (TMOKE) of ultra-thin magnetic dielectric films, achieved through the excitation of strong magnetic resonances due to plasmonic hybridization between Au nanowires and substrate. The coupled system forms two strong magnetic resonances leading to a significant TMOKE signal increase in 30 nm thick ultra-thin magnetic dielectric films, showing potential applications in nanophotonics, magnonics, and spintronics.
Article
Materials Science, Multidisciplinary
Weiwei Zhang, Zhanghua Chen, Vladimir I. Belotelov, Yujun Song
Summary: The Kerr null points of ferromagnetic thin films can be controlled by adjusting the thickness of different material layers. The introduction of non-ferromagnetic materials can enhance the Kerr effect of the ferromagnetic thin films.
Article
Physics, Multidisciplinary
Mansoureh Amanollahi, Mehdi Zamani
Summary: In this paper, a novel structure composed of an all-magneto-optical periodic grating is presented to enhance the transverse magneto-optical Kerr effect (TMOKE), which does not require the use of noble metals. The proposed structure can be utilized for bio-sensing applications by detecting changes in the refractive index of the analyte medium through monitoring of the TMOKE. The advantage of our idea lies in the simultaneous operation of the magneto-optic layer as a sensing layer, leading to extreme TMOKE in a magneto-optical grating.
Article
Nanoscience & Nanotechnology
Ning Ding, Kunihiro Yananose, Carlo Rizza, Feng-Ren Fan, Shuai Dong, Alessandro Stroppa
Summary: We studied the magneto-optical Kerr effect (MOKE) in a two-dimensional heterostructure CrI3/In2Se3/CrI3 using density functional theory calculations and symmetry analysis. The mirror and time-reversal symmetries are broken by the spontaneous polarization in the In2Se3 ferroelectric layer and the antiferromagnetic ordering in the CrI3 layers, thereby activating MOKE. Our results demonstrate that the Kerr angle can be reversed by either the polarization or the antiferromagnetic order parameter. This suggests that ferroelectric and antiferromagnetic 2D heterostructures could be utilized for compact information storage devices, with the information encoded by the two ferroelectric or the two time-reversed antiferromagnetic states and read optically via MOKE.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Fanji Wang, Kyohei Nakano, Hiroshi Segawa, Keisuke Tajima
Summary: The study found that surface-segregated monolayers (SSMs) can induce changes in the packing of polymer aggregates in films, leading to a dramatic change in excitonic interactions of chiral semiconducting polymers.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Multidisciplinary
M. Jovicevic-Klug, P. Jovicevic-Klug, J. McCord, B. Podgornik
Summary: This study demonstrates the potential of using MOKE microscopy to analyze the microstructure and stress state of martensitic steels, without the need for chemical etching, and even achieving accurate volumetric fraction estimation of retained austenite. By combining MOKE microscopy with other techniques, the residual stress state of steel can be accurately determined, and significant reduction in residual stresses can be achieved through deep cryogenic treatment, providing valuable insights for steel properties research.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Physics, Applied
Dedalo Sanz-Hernandez, Luka Skoric, Miguel Angel Cascales-Sandoval, Amalio Fernandez-Pacheco
Summary: Magneto-optical techniques have been developed as key tools for characterizing magnetic effects at the nanoscale. In this study, the researchers introduce the dark-field magneto-optical Kerr effect (DFMOKE), a technique specifically designed for characterizing three-dimensional magnetic nanostructures. They demonstrate the principles of DFMOKE and modify a standard focused MOKE magnetometer to perform measurements. Finally, they showcase the power of DFMOKE by detecting the independent magnetic switching of a single tilted 3D nanowire and a magnetic thin film that surrounds it.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Carmen Martin Valderrama, Mikel Quintana, Ane Martinez-de-Guerenu, Tomoki Yamauchi, Yuki Hamada, Yuichiro Kurokawa, Hiromi Yuasa, Andreas Berger
Summary: This comprehensive experimental study examines the limiting factors and physical mechanisms affecting the performance of transverse magneto-optical Kerr effect (T-MOKE) ellipsometry, focusing on achieving high sensitivity and reduced acquisition times. It is found that the best sensitivity is obtained with incident light polarization with balanced s-p components. The study also explores alternative measurement strategies and finds that the method's theoretical description accurately captures data for any s-p combination of the incoming light.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Rehana Gul, Hazrat Ali, M. Imtiaz Khan, Rafi Ud Din, Muhammad Shafiq, Bin Amin, Mahidur R. Sarker, Sawal Hamid Md Ali
Summary: This study examines the magneto-optical and image state rotation of left and right circularly plane-polarized light pulse through a double Lambda-type four-level configuration of Rubidium atom using Kerr field and Doppler broadening. The experiment shows that enhanced and lossless rotation can be achieved by applying a control field, and almost complete polarization rotation can be observed under specific conditions.
RESULTS IN PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Xinchao Cui, Chong Lu, Chunping Liu, Wenzhong Liu
Summary: In this paper, a new concept of using magnetic nanoparticles as magneto-optical markers is proposed and a magneto-optical gate effect is explored. A high-sensitivity detection method for magnetic nanoparticles is developed based on this principle.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Chemistry, Multidisciplinary
Zhifang Wang, Daniel Martin-Jimenez, Qigang Zhong, Daniel Ebeling, Andre Schirmeisen, Hong Wang, Wenchong Wang, Lifeng Chi
Summary: A method is reported to achieve high-resolution patterning and orientation control of crystalline organic thin films using Au patterned SiO2 substrates.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Optics
B. F. Diaz-Valencia
Summary: This work theoretically demonstrates a significant enhancement of the transversal magneto-optical Kerr effect in a type II hyperbolic metamaterial through excitation of the lowest order-bulk plasmon polariton mode, leading to high localization of the electromagnetic field inside the metamaterial.
Article
Chemistry, Multidisciplinary
Wan-Rong Geng, Yun-Long Tang, Yin-Lian Zhu, Yu-Jia Wang, Bo Wu, Li-Xin Yang, Yan-Peng Feng, Min-Jie Zou, Tong-Tong Shi, Yi Cao, Xiu-Liang Ma
Summary: This study demonstrates the existence of multi-field-driven magnetoelectric-optical coupling mediated by ferroelastic switching at room temperature. It provides a framework for designing potential multifunctional magnetoelectric devices.
ADVANCED MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Habibur Rahman, Meezan Ahmad, Ubaid Ullah, Haseena Bibi, Hazrat Ali, Saeed Haddadi
Summary: The impacts of cross-Kerr non-linearity and Doppler broadening on the magneto-optical rotation induced in surface plasmon polaritons are investigated. It is found that this effect can be leveraged for advantageous implementations in various fields.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
V. P. Kothavale, A. Sharma, R. P. Dhavale, V. D. Chavan, S. R. Shingte, O. Selyshchev, T. D. Dongale, H. H. Park, D. R. T. Zahn, G. Salvan, P. B. Patil
Summary: In this study, Fe3O4 MNPs were functionalized with thiol (-SH) and carboxylic (-COOH) group using meso-2,3-dimercaptosuccinic acid (DMSA). The MNP-DMSA nanoadsorbent showed effective adsorption of Pb(II), Ni(II), and Cd(II) heavy metal ions simultaneously. The adsorption behavior followed Langmuir and pseudo-second order models, and the nanoadsorbent exhibited good reusability.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Review
Physics, Condensed Matter
Volodymyr Dzhagan, Alexander P. Litvinchuk, Mykhailo Ya Valakh, Dietrich R. T. Zahn
Summary: Ternary and quaternary metal-chalcogenides, such as CuInS2 and Cu2ZnSn(S,Se)(4), have gained significant attention for their applications in alternative energy conversion and light-emitting devices. These compounds offer more sustainable and affordable solutions compared to traditional semiconductors. However, their tolerance to non-stoichiometric compositions and polymorphism can lead to undesirable coexistence of different compounds and point defects, posing challenges for practical applications. Raman spectroscopy has emerged as a powerful tool for structural diagnostics and characterization of these compounds, especially in the context of nanostructures. This review aims to summarize the current knowledge on the phonon spectra and the capabilities of Raman and IR spectroscopies in characterizing these promising families of compounds.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Polymer Science
Doan Vu, Wen Liang Tan, Lu He, Alexander Ehm, Dietrich R. T. Zahn, Christopher R. McNeill
Summary: We report the discovery of a third crystalline polymorph of the electron-transporting conjugated polymer P(NDI2OD-T2), called form III, which exhibits an end-on texture. This new polymorph is characterized by the incorporation of two monomer units along the backbone-stacking direction, resulting in a doubling of the unit cell c axis. The formation of form III crystallites is achieved by melt annealing a thin film followed by slow cooling. Analysis using grazing-incidence wide-angle X-ray scattering (GIWAXS) and peak simulation confirms the unique packing of this polymorph. This discovery presents an exciting opportunity to study the structure/function relationships of this important semiconducting polymer.
Article
Chemistry, Multidisciplinary
Ermes Peci, Michele Magnozzi, Lorenzo Ramo, Marzia Ferrera, Domenica Convertino, Simona Pace, Giorgio Orlandini, Apoorva Sharma, Ilya Milekhin, Georgeta Salvan, Camilla Coletti, Dietrich R. T. Zahn, Francesco Bisio, Maurizio Canepa
Summary: The opto-electronic properties of 2D semiconducting materials can be manipulated by engineering the atomic-scale environment. This study investigates the dielectric function of WS2 in different stacking configurations, obtaining reliable results through spectroscopic ellipsometry and optical modeling. The spectral position of excitonic features in WS2 is identified, showing significant redshifts depending on the stacking configuration. These findings provide a consistent reference for the dielectric function of WS2 in vdW stacking configurations, enabling reliable predictions of the optical response.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Yevhenii Havryliuk, Volodymyr Dzhagan, Anatolii Karnaukhov, Oleksandr Selyshchev, Julia Hann, Dietrich R. T. Zahn
Summary: In this study, the composite films of Cu2ZnSnS4 (CZTS) nanocrystals (NCs) with PEDOT:PSS were investigated. The structural stability of both NCs and polymers in the composite films with different ratios was studied. It was found that CZTS NCs and PEDOT:PSS mutually influence each other in the composite. The thermoelectric properties of PEDOT:PSS/CZTS composite films were higher compared to the films consisting of bare materials and can be further improved with the addition of DMSO. However, the presence of NCs in the polymer deteriorates its structural stability when subjected to flash lamp annealing or laser treatment.
Article
Physics, Applied
Yang Pan, Lu He, Ilya Milekhin, Alexander G. Milekhin, Dietrich R. T. Zahn
Summary: In this study, the local photoluminescence quenching and enhancement in the quantum tunneling regime at MoSe2/hBN/plasmonic nanostructure interfaces were investigated using monolayer MoSe2/hBN heterostructure on Au nanotriangles as an example. By utilizing tip-enhanced photoluminescence spectroscopy, the nanostructures were resolved and imaged locally. Furthermore, the competing mechanisms of localized surface plasmon resonance, electron tunneling, and highly localized strain were studied to understand the local photoluminescence quenching and enhancement at the nanoscale.
APPLIED PHYSICS LETTERS
(2023)
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
Engineering, Electrical & Electronic
A. Ievtushenko, V Dzhagan, O. Khyzhun, O. Baibara, O. Bykov, M. Zahornyi, V Yukhymchuk, M. Valakh, D. R. T. Zahn, K. Naumenko, P. Zaremba, S. Zagorodnya
Summary: Ag-containing ZnO nanostructures were synthesized on Ag coated Si substrates using atmospheric pressure metal-organic chemical vapour deposition. The relation between structural parameters and chemical composition with photoluminescence properties and electron-phonon coupling was investigated through XRD, XPS, and Raman spectroscopy. The position and width of the phonon Raman peaks and near bandgap PL band were found to be determined by the structural quality of the crystallites. The heat dissipation in the film, influenced by the nanostructure morphology and Ag content, played a crucial role in the behavior of phonon and PL bands.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Yevhenii Havryliuk, Volodymyr Dzhagan, Anatolii Karnaukhov, Oleksandr Selyshchev, Julia Hann, Dietrich R. T. Zahn
Summary: The problem of waste heat in solar panels has led to research on hybrid solar cells that combine photovoltaic and thermoelectric properties. One potential material for this is Cu2ZnSnS4 (CZTS). In this study, CZTS thin films were formed using green colloidal synthesis and subjected to thermal annealing or flash-lamp annealing. The optimal temperature range for obtaining conductive nanocrystalline films and determining reliable thermoelectric parameters was found to be 250-300 ?. The presence of the CuxS phase was found to be important for the electrical and thermoelectric properties of CZTS films obtained in this way.
Article
Chemistry, Multidisciplinary
Volodymyr Dzhagan, Nazar Mazur, Olga Kapush, Oleksandr Selyshchev, Anatolii Karnaukhov, Oleg A. Yeshchenko, Mykola I. Danylenko, Volodymyr Yukhymchuk, Dietrich R. T. Zahn
Summary: This study investigates the influence of the parameters of the shell and interface in semiconductor core/shell nanocrystals (NCs) on their optical properties and charge transfer, using Raman spectroscopy. The results show that the use of thioglycolic acid (TGA) during the synthesis leads to the formation of a CdS shell around the CdTe core in the NCs. The optical absorption and photoluminescence bands of these NCs are determined by the CdTe core, while the far-infrared absorption and resonant Raman scattering spectra are dominated by the vibrations related to the shell.
Review
Chemistry, Multidisciplinary
Oleksandr Stroyuk, Oleksandra Raievska, Dietrich R. T. Zahn, Christoph J. Brabec
Summary: The review summarizes recent reports on highly efficient photoluminescence originating from self-trapped exciton states in various materials, including chalcopyrite ternary quantum dots, polyheptazine carbon nitrides, and lead-free double halide perovskites. The review outlines the photoluminescence features of these self-trapped exciton emitters and discusses the challenges and promising directions for future research.
Article
Chemistry, Physical
Serhiy Kondratenko, Oleksandr I. Datsenko, Danylo Babich, Volodymyr Dzhagan, Yang Pan, Mahfujur Rahaman, Oleksandr Selyshchev, Dietrich R. T. Zahn
Summary: This study presents the fabrication of hybrid 2D-QD MoS2-AgInS2 photoconductive devices by pressing a MoS2 flake onto an AgInS2 QD film. The devices exhibit enhanced photoresponse under continuous and modulated optical excitations, attributed to the built-in electric field near the MoS2/AgInS2 interface. The study demonstrates the potential of these devices for photovoltaic and optoelectronic applications.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Lu He, Dietrich R. T. Zahn, Teresa I. I. Madeira
Summary: Titanium dioxide (TiO2) thin films have photocatalytic properties and can be used for recycling and maintenance. Factors affecting their performance include nanocrystalline size, surface morphology, and phase composition, which need to be better studied and correlated.
Article
Chemistry, Multidisciplinary
Ilya Milekhin, Kirill Anikin, Nina N. Kurus, Vladimir G. Mansurov, Timur V. Malin, Konstantin S. Zhuravlev, Alexander V. Latyshev, Alexander V. Latyshev, Dietrich R. T. Zahn
Summary: We carried out local phonon analysis on single AlN nanocrystals using two complementary imaging spectroscopic techniques: tip-enhanced Raman scattering (TERS) and nano-Fourier transform infrared (nano-FTIR) spectroscopy. The TERS spectra showed strong surface optical (SO) phonon modes, with their intensities having a weak polarization dependence. The electric field enhancement from the plasmon mode of the TERS tip altered the phonon response of the sample, causing the dominance of the SO mode over other phonon modes. TERS imaging allowed for the visualization of the spatial localization of the SO mode. We successfully observed the angle anisotropy of the SO phonon modes in AlN nanocrystals with nanoscale spatial resolution. The frequency position of the SO modes in nano-FTIR spectra was determined by the excitation geometry and the local nanostructure surface profile, as demonstrated by analytical calculations.
NANOSCALE ADVANCES
(2023)
Article
Chemistry, Multidisciplinary
Oleksandr Stroyuk, Oleksandra Raievska, Christoph J. Brabec, Volodymyr Dzhagan, Yevhenii Havryliuk, Dietrich R. T. Zahn
Summary: We propose a new concept of bottom-to-top design of intercalate carbon nitride compounds based on the self-assembly effects of colloidal single-layer carbon nitride (SLCN) sheets. The self-assembly includes the formation of intercalates of NEt4OH during the drying of SLCN colloids and the spontaneous formation of layered hexagonally-shaped networks on mica surfaces. The dynamics of intercalate formation were studied using in situ X-ray diffraction, and the structure of the intercalates was characterized by vibrational spectroscopy. The self-assembly on mica is driven by both the hexagonal symmetry of heptazine units and the templating effect of the mica surface.
