Article
Materials Science, Ceramics
Katy S. Gerace, Michael T. Lanagan, John C. Mauro
Summary: Understanding the mechanisms contributing to dielectric properties of glasses is critical for designing new compositions for microwave frequency applications. In this work, dielectric permittivity was measured for a series of niobiosilicate glasses with varying compositions. The calculations of polarizability and experimental results reveal that SiO2 polarizability depends on the chemistry and connectivity of the glass, which has important implications for designing glass compositions for microwave frequency applications.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
G. Krishna Priya, S. Yusub, A. Ramesh Babu, N. Sree Ram, V. Aruna
Summary: In this study, the physical properties of a glass containing different concentrations of MnO were determined using various analytical methods. The results showed that with increasing MnO content, the glass exhibited enhanced semiconductor properties and a gradual decrease in strength.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2022)
Article
Chemistry, Physical
Sang-Hye Lee, Sang-Min Lee, Jae-Seung Roh
Summary: In this study, milled polyacrylonitrile (PAN)-based carbon fibers (mPCFs) were prepared using a ball milling process, and the resulting structural changes were analyzed using X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM). With increasing ball milling time, the surface crystallinity decreased while the crystallinity inside unbroken fibers increased.
Article
Materials Science, Ceramics
Kazuki Kanehara, Shingo Urata, Sou Yasuhara, Takaaki Tsurumi, Takuya Hoshina
Summary: In this study, the dielectric properties of oxide glasses were investigated for potential applications in high-frequency communications. The results showed that silica glass exhibited low dielectric dispersion, while alkali silicate glasses exhibited high dielectric dispersion. The shape of the dispersion profile depended on the alkali-metal ions, with lighter ions resulting in broader curves and heavier ions resulting in sharper curves. Molecular dynamics simulations and ion dynamics analysis confirmed the experimental data and revealed that alkali-metal ions significantly affect the dielectric properties of alkali-silicate glasses. Therefore, when fabricating filter devices, a minimal amount of light alkali metals should be used to minimize dielectric loss while maintaining productivity.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Materials Science, Ceramics
Jian Li, Jia Liu, Yongcui Zhang, Wei Sun, Yang Wang, Haitao Wu, Ling Li, Chuanbing Cheng, Yingying Wang, Ke Tan, Futian Liu
Summary: Microstructure design plays a crucial role in regulating the microwave dielectric properties of materials, however, the understanding of frequency temperature stability and related micromechanism remains limited. In this study, a combination of first-principles calculations and experimental observation was used to investigate the correlation among sintering behavior, crystal structure, bonding nature, and microwave dielectric properties of LnPO(4) (Ln = Eu, Pr) ceramics. The research findings systematically clarify the optimized effect and micromechanism of lanthanides on the dielectric properties of monazite ceramics, providing insights into the design and enhancement of microwave dielectric materials.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Yongnian Guan, Kelun Xia, Lelu He, Zhengxiang Gu, Yachen Liang, Jingwei Zhang, Yiming Gui, Xunsi Wang, Shixun Dai, Xiang Shen, Zijun Liu
Summary: Infrared gradient refractive index (GRIN) lenses have great application potential in multispectral imaging systems. This study reports the preparation of various chalcogenide axial GRIN glasses using the hot-pressing diffusion method. The effects of temperature, concentration difference, and diffusion time on the diffusion process are discussed, and the dispersion properties of the GRIN samples are calculated.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Physics, Multidisciplinary
V. A. Astapenko
Summary: A consistent microscopic quantum approach is used to describe the interaction between ultrashort electromagnetic pulses and matter, leading to a macroscopic formula for energy dissipation. This formula is applied to study the energy transfer features of different types of ultrashort pulses to a solid target.
Article
Materials Science, Ceramics
Thiruvilla S. Mahadevan, Jincheng Du
Summary: The long-term chemical durability of borosilicate glasses is achieved through the formation of a porous aluminosilicate gel layer, which limits water transport and corrosion. Understanding the porous silicate gel layer is crucial for elucidating the corrosion mechanism of these glasses and designing new glass compositions. The use of charge scaling techniques is effective for generating porous structures with controllable pore morphologies. The porosities and pore size distributions of the porous structures are strongly correlated to processing temperature and local atomic structure.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Nuclear Science & Technology
Vincent Cantarel, Isao Yamagishi
Summary: This study investigates the interface between ordinary Portland cement and geopolymer. It is found that immersion in the activation solution induces dendritic carbonation in the cement structure, while embedding in geopolymer creates a dense, impermeable interface. However, this brittle interface can rupture under intense drying.
JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Birampally Kalyani, Navaneetha Pujari, Avula Edukondalu, M. Srinivasa Reddy, C. P. Vardhani
Summary: The AC conductivity and dielectric properties of Li2O-Bi2O3-B2O3-As2O3 glass system were investigated. The results showed that the presence of bismuth reduced the DC conductivity and increased the activation energy. The temperature and frequency dependence of the dielectric modulus exhibited a Debye-type relaxation behavior.
Article
Materials Science, Ceramics
G. H. A. Melo, N. F. Dantas, F. R. Muniz, D. Manzani, M. de Oliveira Jr, F. Pedrochi, A. Steimacher
Summary: This study investigated the influence of ZnO content on the structural and radiation shielding parameters of zinc borophosphate glass. The glass samples were prepared using the melt-quenching technique and their structural characteristics were analyzed using various techniques. The results showed that the replacement of BO4 and PO4 units by BO3 and PO4 1/2 units led to changes in the structural characteristics and an increase in non-bridging oxygen. The density increased by up to 43% and the glass transition temperature showed reduction followed by stability with the replacement of P2O5 by ZnO. The rise in ZnO content also improved the radiation attenuation parameters, making the glass system a suitable choice for high-energy ionizing radiation attenuation.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2023)
Article
Chemistry, Multidisciplinary
Qianchi Feng, Dongshan Wei, Yudan Su, Zhiguang Zhou, Feng Wang, Chuanshan Tian
Summary: The study reveals the significant impact of out-of-plane coupling on thermal properties of graphene, as well as the reduction of density of states for longer wavelength out-of-plane vibrations when graphene is supported on an alkane substrate. The negative thermal expansion coefficient of freestanding graphene decreases when out-of-plane rippling is suppressed.
Article
Chemistry, Physical
Rayan Zaiter, Marc Dussauze, Marcelo Nalin, Evelyne Fargin, Frederic Adamietz, Sylvain Danto, Olivier Toulemonde, Thierry Cardinal
Summary: A series of new transparent and magnetic barium gallogermanate glasses with different Gd2O3 contents were synthesized and characterized. The addition of Gd2O3 affected the glass structure and magnetic properties. These glasses have the potential to be used in optical fiber production.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Ceramics
Zhenjun Qing, Huapeng Zou, Xin Zhou, Haiyan Li, An Liu, Shumin Duan, Yingxiang Li, Sen Peng
Summary: Li2Co2Mo3O12 (LCMO) ceramics were synthesized using the solid-state reaction method, and their microwave dielectric properties and influencing factors were studied. It was found that ionic polarizability was the main factor affecting the dielectric constant (er), while relative density had a significant impact on the quality factor (Q x f). In addition, the microwave dielectric properties of LCMO ceramics were closely related to ionicity, lattice energy, bond energy, and thermal expansion coefficient of chemical bonds.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Multidisciplinary
V. L. Vilesh, G. Subodh
Summary: The study reports on the structural and microwave dielectric properties of oxygen-deficient double perovskites, Ba2Li1-xTe1+xO5.5+delta, demonstrating thermal stability and potential value for low-temperature co-fired ceramics applications.
MATERIALS RESEARCH BULLETIN
(2021)
Article
Optics
Ehsan Alimohammadian, Kim Lammers, Alessandro Alberucci, Gligor Djogo, Chandroth P. Jisha, Stefan Nolte, Peter R. Herman
Summary: The formation of volumetric nanogratings in fused silica by femtosecond laser pulses allows for manipulation of physical shape and optical properties. The nanogratings follow the elongation effects induced by conical-shaped phase fronts, enabling a scaling up of the writing volume. Control of the conical phase front angle provides flexible ways to tune macroscopic optical properties.
Article
Optics
Moritz Bartnick, Gayathri Bharathan, Thorsten A. Goebel, Ria G. Kraemer, Stefan Nolte, Camille-Sophie Bres
Summary: We have developed a widely tunable mode-locked thulium-doped fiber laser based on a robust chirped fiber Bragg grating (CFBG). By applying mechanical tension and compression, the CFBG achieved an overall tunability of 20.1 nm, ranging from 2022.1 nm to 2042.2 nm. The mode-locked pulse train from this fiber laser has a repetition rate of 9.4 MHz, average power of 12.6 dBm, and pulse duration between 9.0 ps and 12.8 ps. This is the first demonstration of a tunable mode-locked thulium-doped fiber laser operating beyond 2 μm using a CFBG as a wavelength-selective element.
Article
Optics
Xiaodong Zhao, Matthias Baudisch, Marcus Beutler, Thomas Gabler, Stefan Nolte, Roland Ackermann
Summary: We present an optical parametric amplifier (OPA) that generates pulses with a maximum energy of approximately 200 μJ in the wavelength range of 700-950 nm and duration of about 1 ps. The OPA is driven by a 1 ps pulse with an energy of approximately 2.5 mJ at a frequency of 1 kHz, provided by a commercial thin-disk laser. By using the output pulse of the OPA as a pump, the thin-disk laser generates Stokes light at 1030 nm and uses the second harmonic (515 nm) as a probe for investigating coherent anti-Stokes Raman scattering (CARS) of N-2 and CO2 at different temperatures.
Article
Optics
Anne-Sophie Munser, Marcus Trost, Sven Schroeder, Martina Graf, Miriam A. Rosenbaum, Andreas Tuennermann
Summary: Due to its high sensitivity and quick measurement principle, angle-resolved scattering (ARS) measurements show promising potential as a rapid analysis tool for bacterial cells, especially at small sample sizes and low cell numbers. This study has demonstrated that scattered light from various bacterial cell samples can be analyzed at the single-cell level, which is a significant benefit compared to time-consuming conventional methods that require hours or days of cellular growth. With the proposed setup and data analysis method, it is possible to detect scatter differences among cell types as well as measure cell concentration.
Article
Physics, Applied
Markus Blothe, Maxime Chambonneau, Stefan Nolte
Summary: In this study, laser-based amorphization on the back surface of a crystalline silicon sample was investigated. By utilizing laser irradiation and Bessel beam shaping, the crystalline silicon was transformed into an amorphous state, resulting in the formation of subwavelength periodic surface structures. This research provides new possibilities for processing in-built microelectronic devices.
APPLIED PHYSICS LETTERS
(2022)
Article
Optics
Gia Quyet Ngo, Emad Najafidehaghani, Ziyang Gan, Sara Khazaee, Malte Per Siems, Antony George, Erik P. Schartner, Stefan Nolte, Heike Ebendorff-Heidepriem, Thomas Pertsch, Alessandro Tuniz, Markus A. Schmidt, Ulf Peschel, Andrey Turchanin, Falk Eilenberger
Summary: This study demonstrates a method to achieve second-harmonic generation in functionalized optical fibers by directly growing highly nonlinear MoS2 monolayers on the fiber's core. The approach is scalable and can be generalized to other materials and waveguide systems.
Article
Materials Science, Multidisciplinary
Andreas Tuennermann, Carsten Momma, Stefan Nolte
Summary: Ultrashort pulse lasers have been widely used in precise micromachining. This article presents a brief perspective on the development of this innovative technology from the 1990s until today.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Shawon Alam, Pallabi Paul, Vivek Beladiya, Paul Schmitt, Olaf Stenzel, Marcus Trost, Steffen Wilbrandt, Christian Muehlig, Sven Schroeder, Gabor Matthaeus, Stefan Nolte, Sebastian Riese, Felix Otto, Torsten Fritz, Alexander Gottwald, Adriana Szeghalmi
Summary: Absorption losses and laser-induced damage threshold (LIDT) are the main limitations for the development of optical coatings for high-power laser optics. This study developed heterostructures using sub-nanometer thin films of SiO2 and HfO2 with the plasma-enhanced atomic layer deposition (PEALD) technique. Various thin-film characterization techniques were employed to extract optical constants, residual stress, layer formation, and functional groups of the heterostructures. The heterostructures showed tunable refractive index, bandgap, improved optical losses, and LIDT properties.
Article
Optics
Abhik Chakraborty, Parijat Barman, Ankit Kumar Singh, Xiaofei Wu, Denis A. Akimov, Tobias Meyer-Zedler, Stefan Nolte, Carsten Ronning, Michael Schmitt, Juergen Popp, Jer-Shing Huang
Summary: Plasmonic enhancement of nonlinear light-matter interaction can be achieved by optimizing resonant plasmonic modes that match the wavelengths involved in the nonlinear optical process. This study investigates the generation and enhancement of broadband four-wave mixing in a plasmonic azimuthally chirped grating (ACG), which allows for control of near and far field interactions across a wide range of wavelengths. The mechanism responsible for field enhancement in the ACG platform depends on the interplay between groove geometry and grating periodicity. This work elucidates the collective contribution of localized surface plasmon resonance and plasmonic surface lattice resonance to the enhancement of broadband FWM in the ACG.
LASER & PHOTONICS REVIEWS
(2023)
Article
Optics
Evgeny A. Perevezentsev, Malte Per Siems, Daniel Richter, Ivan B. Mukhin, Ria G. Kraemer, Anton I. Gorokhov, Mikhail R. Volkov, Stefan Nolte
Summary: The first steps towards developing and characterizing next-generation chirped volume Bragg gratings (CVBGs) using fs laser inscription were taken. CVBGs with a 3 x 3 mm2 aperture and a length of almost 12 mm were successfully created on fused silica. Despite the polarization and phase distortions caused by mechanical stresses, a possible solution to this problem was proposed. The small change in the linear absorption coefficient of fused silica allows for the utilization of these gratings in high average power lasers.
Article
Optics
Fatemeh Abtahi, Pallabi Paul, Sebastian Beer, Athira Kuppadakkath, Anton Pakhomov, Adriana Szeghalmi, Stefan Nolte, Frank Setzpfandt, Falk Eilenberger
Summary: Second-harmonic generation (SHG) is observed in periodic stacks of alternating, subwavelength dielectric layers due to the broken symmetry at the surface. The surface SHG is significantly enhanced by the large number of surfaces in these stacks. Experimental results on SiO2/TiO2 multilayer stacks grown by PEALD demonstrate substantial SHG under large angles of incidence, surpassing that of simple interfaces. The experimental results are in agreement with theoretical calculations.
Article
Optics
Xiaodong Zhao, Andre Boden, Stefan Nolte, Roland Ackermann
Summary: We investigate the spectral properties of filamentation induced by ps laser in air using a thin-disk based amplifier with a central wavelength of 1030 nm, maximum pulse energy of 60 mJ, and a repetition rate of 1 kHz. The broad spectrum generated by filamentation is found to be capable of exciting ro-vibrational Raman transitions in N2, O2, and CH4. We probe the excitation using the second harmonic (515 nm) to generate CARS signals in air, and study the influence of optical windows on the CARS signal for combustion and gasification diagnostics applications.
Article
Materials Science, Multidisciplinary
Maxime Chambonneau, Qingfeng Li, Markus Blothe, Stree Vithya Arumugam, Stefan Nolte
Summary: Although ultrafast laser welding is not suitable for joining silicon samples due to nonlinear propagation effects, these limitations can be overcome by enhancing local absorption at the interface through metallic nanolayer deposition. By combining the enhanced absorption with filament relocation during ultrafast laser irradiation, efficient joining of silicon samples is achieved. Shear joining strengths exceeding 4 MPa can be obtained with 21 nm gold nanolayers, promising applications in microelectronics, optics, and astronomy.
ADVANCED PHOTONICS RESEARCH
(2023)
Article
Optics
Chandroth P. Jisha, Stree Vithya Arumugam, Lorenzo Marrucci, Stefan Nolte, Alessandro Alberucci
Summary: We investigate waveguides based on the Pancharatnam-Berry phase, obtained by rotation of the optic axis in a birefringent medium. We study the case where accumulation of geometric phase is present. The interplay between different contributions to the optical potential is addressed and the polarization structure of the quasimodes is observed to evolve continuously.
Proceedings Paper
Optics
Arno Klenke, A. Steinkopff, C. Aleshire, C. Jauregui, Stefan Kuhn, Johannes Nold, Christian Hupel, Sigrun Hein, Steffen Schulze, Nicoletta Haarlammert, Thomas Schreiber, Andreas Tuennermann, Jens Limpert
Summary: In this paper, a rod-type, Ytterbium-doped, multicore fiber with 4x4 cores is presented. This fiber is used in a CPA setup for coherent beam combination of femtosecond pulses. High average powers of up to 507 W after combination and compression are achieved at 10 MHz repetition rate. A high combination efficiency of 85% is realized together with excellent beam quality. Additionally, up to 600 µJ pulse energy is measured in a lower repetition rate configuration.
FIBER LASERS XIX: TECHNOLOGY AND SYSTEMS
(2022)