Article
Materials Science, Multidisciplinary
Ying Song, Yuwei Shan, Weiming Wang, Kainan Chang, Ze Zheng, Zhiming Shi, Dabing Li, Jin Luo Cheng
Summary: The second harmonic generation (SHG) in mechanically exfoliated, few-layer ReS2 samples is investigated. The presence of SHG is observed only in even-layer samples with (AB(y))(n) stacking order. The spectra are greatly enhanced when the fundamental photon energy matches exciton levels, and the polarization dependence and wavelength dependence of each susceptibility component are different.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Biochemistry & Molecular Biology
A. A. Gopal, A. Kazarine, J. M. Dubach, P. W. Wiseman
Summary: Nonlinear microscopy utilizes nonlinear interactions between light and matter to image fluorescence and scattering in biological tissues, requiring high peak intensities and spatial confinement for deep imaging. This technique offers various contrast mechanisms and instrumentation for different purposes.
INTERNATIONAL JOURNAL OF BIOCHEMISTRY & CELL BIOLOGY
(2021)
Article
Dermatology
Mercedes Sendin-Martin, Jasmine Posner, Ucalene Harris, Matthew Moronta, Julian Conejo-Mir Sanchez, Sushmita Mukherjee, Milind Rajadhyaksha, Kivanc Kose, Manu Jain
Summary: Basal cell carcinoma (BCC) is the most common skin cancer, and non-invasive in vivo technologies such as multiphoton microscopy (MPM) can aid in diagnosing and prognosticating these tumors. This study explored the potential of MPM to differentiate collagen changes associated with different BCC subtypes compared to normal skin structures and benign lesions. The results showed that collagen distribution is more aligned surrounding BCCs nests compared to normal structures and benign lesions, and collagen is orientated more parallelly surrounding indolent BCC subtypes versus those with aggressive behavior.
EXPERIMENTAL DERMATOLOGY
(2023)
Article
Oncology
Danielle E. Desa, Wencheng Wu, Robert M. Brown, Edward B. Brown, Robert L. Hill, Bradley M. Turner, Edward B. Brownn
Summary: This study assessed the impact of neoadjuvant chemotherapy on tumor collagen in breast cancer patients. The results showed that chemotherapy affects tumor extracellular collagen in a subtype-specific manner and alters some prognostic signatures. This may have implications for the clinical utility of these signatures.
Article
Materials Science, Multidisciplinary
Zakaniaina Rajaofara, Philippe Leproux, Marc Dussauze, Alessandro Tonello, Vincent Rodriguez, Lara Karam, Hideaki Kano, Jean-Rene Duclere, Vincent Couderc
Summary: Multiplex coherent anti-stokes Raman scattering (M-CARS) and second harmonic generation (SHG) techniques were used to map the nonlinear optical susceptibility of a thermally microimprinted niobium borophosphate glass. The study revealed a systematic reduction in the nonresonant third order nonlinear susceptibility in poled areas, possibly due to sodium depletion. This reduction in susceptibility was linked to a decrease in matter density and linear refractive index in the poled regions.
OPTICAL MATERIALS EXPRESS
(2021)
Article
Multidisciplinary Sciences
Juo-Nang Liao, Wei-Liang Chen, Chao-Yuan Lo, Man-Hong Lai, Huang-Lung Tsai, Yu-Ming Chang
Summary: In this study, a nondestructive method using two-photon fluorescence and second-harmonic generation imaging was demonstrated to quantify starch granules within chloroplasts of intact leaves across a day-night cycle. The results provided micron scale spatial resolution of starch distribution within leaves and showed starch circadian patterns consistent with previous studies. This method is a potential tool for revealing the real-time heterogeneity of starch circadian rhythm in leaf cells without the need for destructive sample preparation.
SCIENTIFIC REPORTS
(2022)
Review
Biochemistry & Molecular Biology
Giulia Borile, Deborah Sandrin, Andrea Filippi, Kurt I. Anderson, Filippo Romanato
Summary: Multiphoton microscopy has been actively used in biomedical research for the past 30 years, offering label-free imaging and a range of applications. This technique, including two-photon autofluorescence and harmonic generation, provides versatile and detailed sample analysis for various research fields. The future of label-free multiphoton microscopy holds promise for further advancements in the study of biological samples.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
Muyang Huang, Bowen Yao, Huating Liu, Siwei Luo, Zongyu Huang, Jianxin Zhong, Qiaoliang Bao, Xiang Qi
Summary: Black phosphorus (BP) exhibits significant saturable absorption and other unique properties in nonlinear optical effects, making it suitable for nonlinear optical elements and photonic devices. However, its inversion symmetry prohibits second harmonic generation (SHG) emission. In this study, we introduce emerging SHG emission in BP by exposing it to oxygen to break the inversion symmetry. The intensity of SHG signal is dependent on the thickness and exposure time, with thinner BP flakes showing a faster SHG intensity change rate. This study provides insights into modulating the SHG emission of BP and potentially other inversion symmetric crystals.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2023)
Review
Dermatology
Ke-Jun Chen, Yang Han, Zi-Yi Wang, Yong Cui
Summary: Non-invasive optical examination is vital in dermatology for diagnosis, management, and research. Multiphoton microscopy uses submicron technology to stimulate autofluorescence and provides insights into cellular structure, redox status, and collagen fibers in the skin. This review highlights the principles and application of multiphoton microscopy in studying various skin conditions.
EXPERIMENTAL DERMATOLOGY
(2023)
Article
Biochemical Research Methods
Radu Hristu, Stefan G. Stanciu, Adrian Dumitru, Bogdan Paun, Iustin Floroiu, Mariana Costache, George A. Stanciu
Summary: Second harmonic generation (SHG) microscopy is a powerful tool for tissue characterization and diagnostics in medicine, particularly for mapping collagen structure for diagnosis. The study found that H&E staining affects the extraction and use of image parameters specific to polarization-resolved SHG microscopy, potentially leading to different analysis results and impacting diagnostic accuracy.
BIOMEDICAL OPTICS EXPRESS
(2021)
Article
Optics
Li Zhang, Xiao Wu, Zhenzhong Hao, Rui Ma, Feng Gao, Fang Bo, Guoquan Zhang, Jingjun Xu
Summary: This Letter reports the fabrication of lithium niobate-on-insulator ridge waveguides with generalized quasiperiodic poled superlattices using electric field polarization technique and microfabrication techniques. The efficient second-harmonic and cascaded third-harmonic signals were observed in the same device, with normalized conversion efficiency of 1735% W-1 cm-2 and 0.41% W-2 cm-4, respectively. This work opens a new direction for nonlinear integrated photonics based on lithium niobate thin film.
Article
Optics
Jyothsna Konkada Manattayil, Lal A. S. Krishna, Rabindra Biswas, Hyunmin Kim, Varun Raghunathan
Summary: In this study, we demonstrate sub-diffraction imaging in an infrared-sensitive third-order sum frequency generation microscope using the focal-field engineering technique. The presence of a phase mask leads to a reduction in the size of the TSFG central lobe and an improvement in contrast for periodic grating structures. Additionally, the infrared sensitivity of the focus-engineered TSFG microscope is validated through imaging of amorphous Germanium-based structures and polystyrene latex beads. The focus-engineered TSFG process shows promise as an imaging modality with infrared selectivity, improved resolution, and contrast, making it suitable for nanostructure and surface layer imaging.
Article
Nanoscience & Nanotechnology
Rabindra Biswas, Asish Prosad, Lal A. S. Krishna, Sruti Menon, Varun Raghunathan
Summary: This study demonstrates the enhancement of second harmonic generation (SHG) from multilayer structures of gallium selenide (GaSe) flakes integrated with Fabry-Perot structures using hybrid-genetic optimization (HGA). The HGA technique significantly speeds up the design process and achieves 128-fold and 400-fold SHG enhancement in single and double GaSe structures, respectively, compared to a reference sample. The SHG conversion efficiencies obtained from the HGA structures are significantly higher than previous reports on 2D material integrated resonant metasurfaces or Bragg cavities.
Article
Optics
Alexander W. A. Murphy, Zichen Liu, Andrey V. Gorbach, Adelina Ilie, Ventsislav K. Valev
Summary: The study presents the first hyperspectral multiphoton analysis of densely-packed stacks of twisted and/or fused WS2 nanosheets, known as nanomesh, which exhibits scalable, efficient, and broadband optical properties due to double resonances induced by internal defects. This makes the nanomesh a prime candidate for integration into quantum optical technologies.
LASER & PHOTONICS REVIEWS
(2021)
Article
Engineering, Biomedical
J-Y Wang, J. C. Mansfield, S. Brasselet, C. Vergari, J. R. Meakin, C. P. Winlove
Summary: Needle injection is widely used in spinal therapeutic or diagnostic processes, but it has been suspected to cause mild disc degeneration leading to long-term back pain. This study found that needle punctures cause local microscopic damage to collagen and cell nuclei, resulting in progressive damage. The size of the needle used did not significantly affect the damage, with more damage observed using larger needles.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Utku Emre Ali, He Yang, Vladislav Khayrudinov, Gaurav Modi, Zengguang Cheng, Ritesh Agarwal, Harri Lipsanen, Harish Bhaskaran
Summary: This article introduces a technique for reliably transferring individual nanowires onto various platforms and demonstrates their applications on different structures. The versatility of this technique enables easy integration of nanowires into previously seen cumbersome or impractical applications, including TEM studies and in situ electrical, optical, and mechanical characterization.
Article
Chemistry, Physical
Abde Mayeen Shafi, Susobhan Das, Vladislav Khayrudinov, Md Gius Uddin, Er-Xiong Ding, Faisal Ahmed, Zhipei Sun, Harri Lipsanen
Summary: This study reports the van der Waals epitaxy of one-dimensional InP nanowires directly on two-dimensional MoS2 using the VLS method. The high-quality nanowires with high density and yield were successfully grown on MoS2 through optimized growth parameters. The mixed-dimensional heterostructures exhibit strong linear and nonlinear optical responses, including odd-order high harmonic generation up to seventh order.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Yadong Wang, Fadil Iyikanat, Xueyin Bai, Xuerong Hu, Susobhan Das, Yunyun Dai, Yi Zhang, Luojun Du, Shisheng Li, Harri Lipsanen, F. Javier Garcia de Abajo, Zhipei Sun
Summary: We demonstrate optically controlled high-harmonic generation (HHG) in monolayer semiconductors by engineering interband polarization. Our experiments reveal efficient control of HHG in the excitonic spectral region with high modulation depths and ultrafast response speeds. Time-domain theory of the nonlinear optical susceptibilities in monolayer semiconductors further supports our findings.
Article
Multidisciplinary Sciences
Hoon Hahn Yoon, Henry A. Fernandez, Fedor Nigmatulin, Weiwei Cai, Zongyin Vane, Hanxiao Cui, Faisal Ahmed, Xiaoqi Cui, Md Gius Uddin, Ethan D. Minot, Hard Lipsanen, Kwanpyo Kim, Pertti Hakonen, Tawfique Hasan, Zhipei Sun
Summary: This study presents a high-performance computational spectrometer based on a single van der Waals junction, which achieves high accuracy and resolution using an electrically tunable transport-mediated spectral response, providing unprecedented performance for miniaturized applications.
Article
Nanoscience & Nanotechnology
Er-Xiong Ding, Peng Liu, Hoon Hahn Yoon, Faisal Ahmed, Mingde Du, Abde Mayeen Shafi, Naveed Mehmood, Esko I. Kauppinen, Zhipei Sun, Harri Lipsanen
Summary: Fabricating electronic and optoelectronic devices using a facile electrode fabrication process with SWCNT films leads to improved device performance. Dry-transferred SWCNT films as transparent electrodes in Schottky diodes for photodetector applications increase light absorption in photoactive MoS2 channels. The enhanced photodetection is attributed to FN tunneling and internal photoemission of charge carriers excited from indium tin oxide across the MoS2 layer.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Bogdan R. R. Borodin, Prokhor A. A. Alekseev, Vladislav Khayrudinov, Evgeniy Ubyivovk, Yury Berdnikov, Nickolay Sibirev, Harri Lipsanen
Summary: Control over doping at the nanoscale during nanostructure growth is crucial for device fabrication. This study investigates the p (Zn)- and n (Sn)- doping distributions and the formation of 3D p-n junctions in planar GaAs nanowires grown on doped GaAs substrates. Various techniques, including scanning electron microscopy, transmission electron microscopy, and conductive atomic force microscopy, are used to analyze the nanowire morphology and doping distribution. The results show that bipolar transistor-like lateral nanostructures can be formed during p-n or n-p growth on misoriented (001) GaAs substrates, while core-shell field effect transistor-like structures can be synthesized on singular (001) substrates. The effects of substrate misorientation on 3D doping distribution are attributed to the preferential incorporation of dopants in polar side facets compared to a non-polar top (001) facet.
Article
Materials Science, Coatings & Films
Oili M. E. Ylivaara, Andreas Langner, Satu Ek, Jari Malm, Jaakko Julin, Mikko Laitinen, Saima Ali, Sakari Sintonen, Harri Lipsanen, Timo Sajavaara, Riikka L. Puurunen
Summary: This study investigates the effects of residual stress and intrinsic stress on ALD Al2O3 films, finding that post-ALD thermal processing leads to increased residual stress and that AL2O3 grown using plasma ALD has the lowest intrinsic stress. The results suggest that ALD Al2O3 films grown at 200 and 300 degrees C are suitable for applications involving post-ALD thermal processing at 700 degrees C.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Physics, Multidisciplinary
Fei Lou, Xiangpeng Cui, Xinyue Sheng, Chunyan Jia, Shuaiyi Zhang, Xia Wang, Vladislav Khayrudinov, Baitao Zhang, Shande Liu, Wing Yim Tam, Harri Lipsanen, He Yang, Jingliang He
Summary: Various nanophotonic devices based on semiconductor wires with a diameter of several ten nanometers have been studied. The optoelectronics properties and performance of devices based on large-diameter wires were explored by growing micronsized indium antimonide (InSb) wires and examining their nonlinear optical properties within the wavelength range of 0.8-2.8 μm. The InSb microwires (MWs) were shown to work as an effective and robust optical switch within 1-2.8 μm wavelength, opening up possibilities for research on more large-diameter MWs made from other semiconductor materials for photonic and electronic devices.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2023)
Article
Chemistry, Multidisciplinary
Faisal Ahmed, Carlos Rodriguez-Fernandez, Henry A. Fernandez, Yi Zhang, Abde Mayeen Shafi, Md Gius Uddin, Xiaoqi Cui, Hoon Hahn Yoon, Naveed Mehmood, Andreas C. Liapis, Lide Yao, Humeyra Caglayan, Zhipei Sun, Harri Lipsanen
Summary: Developing selective and coherent polymorphic crystals at the nanoscale can be used to design integrated architectures for photonic and optoelectronic applications. In this study, a direct optical writing approach is demonstrated to create polymorphic 2D materials. The polymorphic-engineered MoTe2 shows strong optical contrast and enhanced third harmonic generation intensity, making it suitable for various applications.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Peng Liu, Abu Taher Khan, Er-Xiong Ding, Qiang Zhang, Zhenyu Xu, Xueyin Bai, Nan Wei, Ying Tian, Diao Li, Hua Jiang, Harri Lipsanen, Zhipei Sun, Esko I. Kauppinen
Summary: This study develops a straightforward and scalable method for synthesizing high-purity semiconducting single-walled carbon nanotubes (s-SWCNTs) with small-diameter distribution. Water and carbon dioxide produced during the decomposition of isopropanol act as oxidizing agents to selectively etch metallic SWCNTs, enhancing the production of s-SWCNTs. The fabricated field effect transistors and thin-film transistors based on the synthesized s-SWCNTs demonstrate excellent performance, confirming the feasibility of this method for sustainable synthesis of high-quality s-SWCNTs for electronic devices.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Materials Science, Coatings & Films
Heli Seppanen, Igor Prozheev, Christoffer Kauppinen, Sami Suihkonen, Kenichiro Mizohata, Harri Lipsanen
Summary: The effect of adding atomic layer annealing to a plasma-enhanced atomic layer deposition process of aluminum nitride was investigated. The study examined the refractive index, crystallinity, stoichiometry, and impurity concentrations of the films grown on Si(111) substrates. The additional energy provided by atomic layer annealing enhanced the film quality and density, making it suitable for applications requiring high-quality films at low temperatures.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Chemistry, Analytical
Yifan Zhao, He Yang, Vladislav Khayrudinov, Harri Lipsanen, Xinyang Su, Mei Qi, Baole Lu, Ningfang Song
Summary: We demonstrated a flexible monolithic saturable absorber (SA) for broadband optical modulation, which was prepared by growing GaAs nanowires on a polyimide substrate. The SA showed good linear and nonlinear optical properties, making it suitable for applications such as optical switches. Experimental results showed that the SA achieved efficient laser modulation at 1.0 and 1.5 μm wavelengths.
Article
Chemistry, Multidisciplinary
Abde Mayeen Shafi, Md Gius Uddin, Xiaoqi Cui, Fida Ali, Faisal Ahmed, Mohamed Radwan, Susobhan Das, Naveed Mehmood, Zhipei Sun, Harri Lipsanen
Summary: A deterministic method is proposed to improve the performance of MoTe2 devices by inducing local tensile strain through substrate engineering and encapsulation processes. The approach involves creating hole arrays in the substrate and using atomic layer deposition grown Al2O3 as an additional back-gate dielectric layer on SiO2. This study presents a novel technique to enhance carrier mobility in MoTe2 FETs, offering promising prospects for improving 2D material performance in electronic applications.
Article
Chemistry, Physical
Kirill Isakov, Olli Sorsa, Taina Rauhala, Santeri Saxelin, Tanja Kallio, Harri Lipsanen, Christoffer Kauppinen
Summary: With the development of microscale and standalone electronic devices, the demand for microscale energy storage is increasing. In this work, the capacitance of porous silicon (PS) supercapacitor electrodes was enhanced up to 4x by adding a new high-surface-area nanoelectrode. The grass-like alumina (GLA) nanoelectrode showed remarkable stability and increased the capacitance of PS supercapacitors fourfold.
Article
Materials Science, Multidisciplinary
Vladislav Khayrudinov, Anastasiia Sorokina, Vidur Raj, Nikita Gagrani, Tomi Koskinen, Hua Jiang, Ilkka Tittonen, Chennupati Jagadish, Hark Hoe Tan, Harri Lipsanen, Tuomas Haggren
Summary: This study reports the successful growth of self-catalyzed GaAs nanowires on flexible plastic substrates, which are used to fabricate monolithic light-emitting diodes. The nanowires demonstrate crystalline structure and promising optical properties.
ADVANCED PHOTONICS RESEARCH
(2022)
