Article
Nanoscience & Nanotechnology
Nicholas D. Ignacio, Jameela Fatheema, Yu-Rim Jeon, Deji Akinwande
Summary: Using scanning tunneling microscopy, in situ micro-Raman, and electrical measurements, it is shown that the β phase of In(2)Se(3) can remain stable at room temperature in non-oxidative environments, particularly when encapsulated with materials like graphene. This provides a new method of phase manipulation for phase change memory and emphasizes the importance of passivation in In2Se3 memory devices.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Elliot J. Fuller, David S. Ashby, Celia Polop, Elena Salagre, Bhuvsmita Bhargava, Yueming Song, Enrique Vasco, Joshua D. Sugar, Paul Albertus, Tevfik Onur Mentes, Andrea Locatel, Pilar Segovia, Miguel Angel Gonzalez-Barrio, Arantzazu Mascaraque, Enrique G. Michel, A. Alec Talin
Summary: In this study, isolated LiCoO2 islands were subjected to electrochemical cycling and the spatial distribution of conductive and insulating phases was observed using conductive atomic force microscopy (c-AFM). The research findings show that smaller LCO islands have a higher conductive fraction and surface energy can dominate in smaller islands. Additionally, significant shifts in current flow were observed when force was applied to strain the islands, and the underlying mechanisms for this behavior were discussed. Comparison with photoemission electron microscopy images indicated that strain and morphology become more critical to electrochemical performance as particles approach nanometer dimensions.
Article
Chemistry, Multidisciplinary
Patrick D. Lomenzo, Liam Collins, Richard Ganser, Bohan Xu, Roberto Guido, Alexei Gruverman, Alfred Kersch, Thomas Mikolajick, Uwe Schroeder
Summary: The emergence of ferroelectric and antiferroelectric properties in HfO2 and ZrO2 high-k dielectrics is leading to unexpected technological developments. However, the lack of clear distinction between these behaviors is hindering progress. This study uses band-excitation piezoresponse force microscopy and molecular dynamics to elucidate electric field-induced phase transitions in ZrO2-based antiferroelectrics. The nanoscale phase transitions discovered in this study provide new opportunities for the development of nanoelectronic devices.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Levente Juhasz, Roberto D. Ortuso, Kaori Sugihara
Summary: The study utilized quantitative friction force microscopy to measure the response of polydiacetylene to lateral forces, revealing the necessity of applying shear forces to characterize it at the nanoscale. The experiment confirmed the erroneous nature of the hypothesis regarding the higher force sensitivity at the edges and discovered a correlation between mechanochromism and thermochromism.
Article
Chemistry, Multidisciplinary
Taeko Matsukata, F. Javier Garcia de Abajo, Takumi Sannomiya
Summary: Research on exciting nanospheres to generate circularly polarized light emission along arbitrary directions further demonstrates the feasibility of using free-electron-induced light emission in applications such as quantum communication and encryption.
Article
Thermodynamics
Juhang Cha, Hwijong Shin, Ohmyoung Kwon
Summary: Through this study, we achieved a two-dimensional extension of NP SThM with almost a 20-fold improvement in measurement sensitivity under mild vacuum conditions. Vacuum point scanning thermal microscopy has been proven to be an essential tool in the analysis of nanoscale energy transport and conversion inside nanodevices and nanomaterials.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Optics
Boyang Liu, Zhenghui Liu, Gengzhao Xu, Wentao Song, Chunyu Zhang, Kebei Chen, Sha Han, Xiaojuan Sun, Dabing Li, Ke Xu
Summary: AlGaN is an important material for deep ultraviolet optoelectronic devices and electronic devices. The phase separation on the AlGaN surface, which results in small-scale compositional fluctuations of Al, can degrade the performance of devices. By utilizing the scanning diffusion microscopy method, the Al0.3Ga0.7N wafer was studied to investigate the mechanism of surface phase separation. The results demonstrate that scanning diffusion microscopy is an effective method to analyze the micro-mechanism of AlGaN phase separation.
Article
Physics, Applied
M. Checa, S. M. Neumayer, M. A. Susner, M. A. McGuire, P. Maksymovych, L. Collins
Summary: The proposed advanced scanning probe microscopy approach allows for simultaneous mapping of surface potential, dielectric, and piezoelectric properties on the nanoscale, as well as quantitative mapping of electromechanical properties free of background artifacts. The method has been demonstrated on a chemically phase separated composite sample and shown domain structure evolution during thermally stimulated phase transition.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Razmik A. Hovhannisyan, Sergey Yu Grebenchuk, Denis S. Baranov, Dimitri Roditchev, Vasily S. Stolyarov
Summary: The study uses lateral Josephson junctions (LJJ) to quantify the stray magnetic field of Co-coated cantilevers in magnetic force microscopy (MFM), establishing a spatial map. Based on the findings, integrating LJJs directly on the tips of cantilevers as nanosensors of local magnetic fields in scanning probe microscopes is suggested.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Analytical
David Klenerman, Yuri Korchev, Pavel Novak, Andrew Shevchuk
Summary: The reduction in ion current near a cell surface when a fine pipette approaches allows imaging of cell surface topography with nanoscale resolution without damaging the delicate surface. By combining various methods such as single-channel recording, force application, and fluorescence imaging, there is great potential to image and map live cell surfaces at the nanoscale with high resolution and speed.
ANNUAL REVIEW OF ANALYTICAL CHEMISTRY, VOL 14, 2021
(2021)
Article
Chemistry, Multidisciplinary
Hyungjoon Shim, Geunseop Lee
Summary: Nanoscale phase separation is common in various materials, and in this study, an array of indium wires on Si(111) undergoes a first-order charge-density-wave (CDW) transition with minimal or no phase separation when prepared without indium adatom impurities. However, the presence of indium adatom impurities causes phase separation and blurs the transition. These experimental observations provide insights into nanoscale surface phase transitions.
Article
Chemistry, Analytical
Yasufumi Takahashi, Yuya Sasaki, Takeshi Yoshida, Kota Honda, Yuanshu Zhou, Takafumi Miyamoto, Tomoko Motoo, Hiroki Higashi, Andrew Shevchuk, Yuri Korchev, Hiroki Ida, Rikinari Hanayama, Takeshi Fukuma
Summary: Scanning ion conductance microscopy (SICM) is a promising tool for visualizing the dynamics of nanoscale cell surface topography. However, the lack of guidelines for fabricating nanopipettes with ideal shape has hindered SICM imaging at the submicron scale. In this study, we developed a simple and reproducible method for fabricating nanopipettes with sub-20nm apertures and demonstrated improved spatial resolution for nanoscale time-lapse topographic imaging.
ANALYTICAL CHEMISTRY
(2023)
Review
Physiology
Andrea M. Lopez-Canizales, Aracely Angulo-Molina, Adriana Garibay-Escobar, Erika Silva-Campa, Miguel A. Mendez-Rojas, Karla Santacruz-Gomez, Monica Acosta-Elias, Beatriz Castaneda-Medina, Diego Soto-Puebla, Osiris Alvarez-Bajo, Alexel Burgara-Estrella, Martin Pedroza-Montero
Summary: This article discusses the changes in the membrane of red blood cells caused by storage and irradiation, characterized using various techniques. The experimental results serve as biomarkers of cell aging and storage damage.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Chemistry, Physical
Yuyao Zhang, Xiaoying Zhu, Bokai Zhu, Chiheng Chu, Baoliang Chen
Summary: The hydrophobicity of nanomaterials plays a crucial role in various interfacial phenomena. However, it is challenging to study the high-resolution surface hydrophobicity at the nanoscale. In this study, a chemical force microscopy technique is used to profile in situ hydrophobicity images with nanoscale resolution, providing significant improvement compared to traditional methods. The method is applied to recognize the spatial fine structure hydrophobicity of different materials and reveals new findings regarding the hydrophobicity of graphene oxides (GO) and the influence of wrinkles/edges on hydrophobicity. Furthermore, the technique enables the observation of local oxidation variation during interfacial reactions.
Review
Chemistry, Multidisciplinary
Rongxiu Zhai, Bin Fang, Yaqi Lai, Bo Peng, Hua Bai, Xiaowang Liu, Lin Li, Wei Huang
Summary: Mitochondria play an essential role in the development of diseases and cellular metabolism disorders. Super-resolution imaging is crucial for studying the ultrafine structures and functions of mitochondria. Small-molecule fluorogenic probes have unique properties that make them ideal for super-resolution imaging of mitochondria. This paper summarizes recent advances in small-molecule fluorogenic probes, focusing on their chemical and spectroscopic properties for mitochondrial imaging. Future challenges in this field, including the design principles of small-molecule fluorogenic probes and nanoscopic techniques, are also discussed.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Nikolaos Farmakidis, Nathan Youngblood, June Sang Lee, Johannes Feldmann, Alessandro Lodi, Xuan Li, Samarth Aggarwal, Wen Zhou, Lapo Bogani, Wolfram Hp Pernice, C. David Wright, Harish Bhaskaran
Summary: The authors demonstrate an electrically reconfigurable, ultra-compact, and nonvolatile memory that harmonizes electronics and photonics through localized heat generation and interlocked optical and electrical readout signals, achieving unprecedented energy efficiency.
Article
Optics
James Y. S. Tan, Zengguang Cheng, Johannes Feldmann, Xuan Li, Nathan Youngblood, Utku E. Ali, C. David Wright, Wolfram H. P. Pernice, Harish Bhaskaran
Summary: This study demonstrates a form of backpropagation-free learning using an integrated photonic platform. By utilizing phase-change materials and on-chip cascaded directional couplers, the researchers develop a machine learning framework based on single-element associations. This approach reduces computational burden and increases learning speed while offering higher bandwidth.
Article
Multidisciplinary Sciences
Syed Ghazi Sarwat, Frank Brueckerhoff-Plueckelmann, Santiago Garcia-Cuevas Carrillo, Emanuele Gemo, Johannes Feldmann, Harish Bhaskaran, C. David Wright, Wolfram H. P. Pernice, Abu Sebastian
Summary: With the digitization of modern life and scientific tools, the generation of data is growing exponentially, requiring fast and efficient statistical processing. This paper introduces a novel computational paradigm through the development of an integrated phase-change photonics engine. By exploiting the properties of phase-change cells and optics, the engine enables fully parallel and colocated temporal correlation detection computations. Experimental demonstrations on Twitter and data centers showcase the use of high-speed integrated photonics in accelerating statistical analysis methods.
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
Multidisciplinary Sciences
June Sang Lee, Nikolaos Farmakidis, C. David Wright, Harish Bhaskaran
Summary: This study introduces hybridized-active-dielectric nanowires for polarization-selective tunability and demonstrates the ability to modulate conductance and perform matrix-vector multiplication using polarization as a parameter. This concept can be generalized to other materials and has potential in various applications.
Article
Chemistry, Multidisciplinary
Eugene Jia Hao Soh, Hippolyte P. A. G. Astier, Dan Daniel, Jia Qing Isaiah Chua, Ali Miserez, Zian Jia, Ling Li, Sean J. O'Shea, Harish Bhaskaran, Nikodem Tomczak, Christian A. Nijhuis
Summary: In this study, we demonstrate the direct manipulation and control of liquid metal droplets using an atomic force microscope, achieving repeated contact and separation with self-assembled monolayers in different environments. We successfully create well-defined contact areas of liquid droplets on alkanethiolate SAMs in ethanol, and achieve smaller geometric contact areas in air compared to previous studies.
Article
Nanoscience & Nanotechnology
Frank Brueckerhoff-Plueckelmann, Ivonne Bente, Daniel Wendland, Johannes Feldmann, C. David Wright, Harish Bhaskaran, Wolfram Pernice
Summary: Integrated neuromorphic photonic circuits aim to power complex artificial neural networks in an energy and time efficient way. Scaling photonic circuits to match the requirements of modern ANNs remains challenging. A proposed time multiplexed matrix processing scheme virtually increases the size of a physical photonic crossbar array without requiring additional electrical post-processing, enabling high-speed and high-accuracy matrix vector multiplications.
Article
Chemistry, Multidisciplinary
Mengyun Wang, June Sang Lee, Samarth Aggarwal, Nikolaos Farmakidis, Yuhan He, Tangsheng Cheng, Harish Bhaskaran
Summary: The field of flat optics using nanostructured metasurfaces has made great progress in the last decade. Chalcogenide phase-change materials (PCMs) have shown potential in realizing reconfigurable metasurfaces. This study demonstrates active polarization-insensitive phase-change metalenses at near-IR wavelengths using a low-loss PCM Sb2Se3. The material's ultralow-loss nature opens up new possibilities for optical communications, multi-depth imaging, beam steering, optical routing, and holography.
Article
Optics
Ivonne Bente, Frank Brueckerhoff-Plueckelmann, J. Rasmus Bankwitz, Daniel Wendland, Emma Lomonte, Francesco Lenzini, C. David Wright, Harish Bhaskaran, Wolfram H. P. Pernice
Summary: Reconfigurable photonic integrated circuits, by combining electro-optical tunability and nonvolatile attenuation through functional materials, are proposed for optical pattern generation. The use of phase-change material Ge2Sb2Te5 (GST) as a tunable attenuator in an integrated photonic circuit enables the generation of short optical pulses based on inverse discrete Fourier transform principles.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Nikolaos Farmakidis, Hao Yu, June Sang Lee, Johannes Feldmann, Mengyun Wang, Yuhan He, Samarth Aggarwal, Bowei Dong, Wolfram H. P. Pernice, Harish Bhaskaran
Summary: Integrated photonic circuits (PICs) have gained significant attention and commercial success in the past decade. However, the spectral characteristics of high-quality resonances in PICs are sensitive to small variations in fabrication and material constants, limiting their applicability. In this study, we propose a scalable solution using existing lithography tools to permanently modulate the waveguide's effective index by exploiting the volume shrinkage exhibited by certain polymers during the semiconductor fabrication process. This technique enables broadband and lossless tuning, making it suitable for various applications in optical computing, telecommunications, and free-space optics.
Article
Nanoscience & Nanotechnology
Ghazi Sarwat Syed, Yingqiu Zhou, Jamie Warner, Harish Bhaskaran
Summary: We introduce a two-dimensional heterojunction-based optomemristive neuron that demonstrates nonlinear and rectified integration of information, as well as optically broadcasting. This neuron has potential applications in machine learning, particularly in winner-take-all networks.
NATURE NANOTECHNOLOGY
(2023)
Review
Optics
Nathan Youngblood, Carlos A. Rios Ocampo, Wolfram H. P. Pernice, Harish Bhaskaran
Summary: Memristors in electronics have shown great potential in various applications, and the ability to vary conductance has led to interest in memristors. In the field of photonic computing, optical analogues of memristors, which modulate light transmission in integrated circuits, are being pursued. This review focuses on recent progress and the current state of integrated optical memristors.
Article
Multidisciplinary Sciences
Wen Zhou, Bowei Dong, Nikolaos Farmakidis, Xuan Li, Nathan Youngblood, Kairan Huang, Yuhan He, C. David Wright, Wolfram H. P. Pernice, Harish Bhaskaran
Summary: This paper reports an in-memory photonic-electronic dot-product engine that decouples electronic programming of phase-change memory cells and enables parallel photonic computation with high-bit operation, low energy consumption, and high accuracy. The developed system achieves high inferencing accuracies in image recognition.
NATURE COMMUNICATIONS
(2023)
Correction
Nanoscience & Nanotechnology
Ghazi Sarwat Syed, Yingqiu Zhou, Jamie Warner, Harish Bhaskaran
NATURE NANOTECHNOLOGY
(2023)
Article
Optics
Samarth Aggarwal, Bowei Dong, Johannes Feldmann, Nikolaos Farmakidis, Wolfram H. P. Pernice, Harish Bhaskaran
Summary: The use of artificial intelligence in tasks like image classification and speech recognition has become an integral part of our lives, necessitating the processing of large amounts of data in real-time. Photonic cores offer ultra-fast convolutional processing by utilizing parallelized matrix-vector multiplications (MVMs) through broadband optical links. This paper proposes and demonstrates a hardware photonic architecture with reduced rank operation, improving scalability and reducing system complexity.