journal
MENU ▼
Read by QxMD icon Read
search

Nature Nanotechnology

journal
https://www.readbyqxmd.com/read/28650442/magnetic-brightening-and-control-of-dark-excitons-in-monolayer-wse2
#1
Xiao-Xiao Zhang, Ting Cao, Zhengguang Lu, Yu-Chuan Lin, Fan Zhang, Ying Wang, Zhiqiang Li, James C Hone, Joshua A Robinson, Dmitry Smirnov, Steven G Louie, Tony F Heinz
Monolayer transition metal dichalcogenide crystals, as direct-gap materials with strong light-matter interactions, have attracted much recent attention. Because of their spin-polarized valence bands and a predicted spin splitting at the conduction band edges, the lowest-lying excitons in WX2 (X = S, Se) are expected to be spin-forbidden and optically dark. To date, however, there has been no direct experimental probe of these dark excitons. Here, we show how an in-plane magnetic field can brighten the dark excitons in monolayer WSe2 and permit their properties to be observed experimentally...
June 26, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28650440/probing-dark-excitons-in-atomically-thin-semiconductors-via-near-field-coupling-to-surface-plasmon-polaritons
#2
You Zhou, Giovanni Scuri, Dominik S Wild, Alexander A High, Alan Dibos, Luis A Jauregui, Chi Shu, Kristiaan De Greve, Kateryna Pistunova, Andrew Y Joe, Takashi Taniguchi, Kenji Watanabe, Philip Kim, Mikhail D Lukin, Hongkun Park
Transition metal dichalcogenide (TMD) monolayers with a direct bandgap feature tightly bound excitons, strong spin-orbit coupling and spin-valley degrees of freedom. Depending on the spin configuration of the electron-hole pairs, intra-valley excitons of TMD monolayers can be either optically bright or dark. Dark excitons involve nominally spin-forbidden optical transitions with a zero in-plane transition dipole moment, making their detection with conventional far-field optical techniques challenging. Here, we introduce a method for probing the optical properties of two-dimensional materials via near-field coupling to surface plasmon polaritons (SPPs)...
June 26, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28650439/2d-materials-brightening-the-dark-excitons
#3
Kian Ping Loh
No abstract text is available yet for this article.
June 26, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28650437/antigen-capturing-nanoparticles-improve-the-abscopal-effect-and-cancer-immunotherapy
#4
Yuanzeng Min, Kyle C Roche, Shaomin Tian, Michael J Eblan, Karen P McKinnon, Joseph M Caster, Shengjie Chai, Laura E Herring, Longzhen Zhang, Tian Zhang, Joseph M DeSimone, Joel E Tepper, Benjamin G Vincent, Jonathan S Serody, Andrew Z Wang
Immunotherapy holds tremendous promise for improving cancer treatment. To administer radiotherapy with immunotherapy has been shown to improve immune responses and can elicit the 'abscopal effect'. Unfortunately, response rates for this strategy remain low. Herein we report an improved cancer immunotherapy approach that utilizes antigen-capturing nanoparticles (AC-NPs). We engineered several AC-NP formulations and demonstrated that the set of protein antigens captured by each AC-NP formulation is dependent on the NP surface properties...
June 26, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28650443/sulfated-glycopeptide-nanostructures-for-multipotent-protein-activation
#5
Sungsoo S Lee, Timmy Fyrner, Feng Chen, Zaida Álvarez, Eduard Sleep, Danielle S Chun, Joseph A Weiner, Ralph W Cook, Ryan D Freshman, Michael S Schallmo, Karina M Katchko, Andrew D Schneider, Justin T Smith, Chawon Yun, Gurmit Singh, Sohaib Z Hashmi, Mark T McClendon, Zhilin Yu, Stuart R Stock, Wellington K Hsu, Erin L Hsu, Samuel I Stupp
Biological systems have evolved to utilize numerous proteins with capacity to bind polysaccharides for the purpose of optimizing their function. A well-known subset of these proteins with binding domains for the highly diverse sulfated polysaccharides are important growth factors involved in biological development and tissue repair. We report here on supramolecular sulfated glycopeptide nanostructures, which display a trisulfated monosaccharide on their surfaces and bind five critical proteins with different polysaccharide-binding domains...
June 19, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28650441/neutrophil-mediated-anticancer-drug-delivery-for-suppression-of-postoperative-malignant-glioma-recurrence
#6
Jingwei Xue, Zekai Zhao, Lei Zhang, Lingjing Xue, Shiyang Shen, Yajing Wen, Zhuoyuan Wei, Lu Wang, Lingyi Kong, Hongbin Sun, Qineng Ping, Ran Mo, Can Zhang
Cell-mediated drug-delivery systems have received considerable attention for their enhanced therapeutic specificity and efficacy in cancer treatment. Neutrophils (NEs), the most abundant type of immune cells, are known to penetrate inflamed brain tumours. Here we show that NEs carrying liposomes that contain paclitaxel (PTX) can penetrate the brain and suppress the recurrence of glioma in mice whose tumour has been resected surgically. Inflammatory factors released after tumour resection guide the movement of the NEs into the inflamed brain...
June 19, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28650438/cancer-therapy-neutrophils-traffic-in-cancer-nanodrugs
#7
Satoru Osuka, Erwin G Van Meir
No abstract text is available yet for this article.
June 19, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28650436/monitoring-the-orientation-of-rare-earth-doped-nanorods-for-flow-shear-tomography
#8
Jongwook Kim, Sébastien Michelin, Michiel Hilbers, Lucio Martinelli, Elodie Chaudan, Gabriel Amselem, Etienne Fradet, Jean-Pierre Boilot, Albert M Brouwer, Charles N Baroud, Jacques Peretti, Thierry Gacoin
Rare-earth phosphors exhibit unique luminescence polarization features originating from the anisotropic symmetry of the emitter ion's chemical environment. However, to take advantage of this peculiar property, it is necessary to control and measure the ensemble orientation of the host particles with a high degree of precision. Here, we show a methodology to obtain the photoluminescence polarization of Eu-doped LaPO4 nanorods assembled in an electrically modulated liquid-crystalline phase. We measure Eu(3+) emission spectra for the three main optical configurations (σ, π and α, depending on the direction of observation and the polarization axes) and use them as a reference for the nanorod orientation analysis...
June 19, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28604709/two-dimensional-non-volatile-programmable-p-n-junctions
#9
Dong Li, Mingyuan Chen, Zhengzong Sun, Peng Yu, Zheng Liu, Pulickel M Ajayan, Zengxing Zhang
Semiconductor p-n junctions are the elementary building blocks of most electronic and optoelectronic devices. The need for their miniaturization has fuelled the rapid growth of interest in two-dimensional (2D) materials. However, the performance of a p-n junction considerably degrades as its thickness approaches a few nanometres and traditional technologies, such as doping and implantation, become invalid at the nanoscale. Here we report stable non-volatile programmable p-n junctions fabricated from the vertically stacked all-2D semiconductor/insulator/metal layers (WSe2/hexagonal boron nitride/graphene) in a semifloating gate field-effect transistor configuration...
June 12, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28604708/photodetectors-a-heated-junction
#10
Ming Zhou, Zongfu Yu
No abstract text is available yet for this article.
June 12, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28604707/ultracoherent-nanomechanical-resonators-via-soft-clamping-and-dissipation-dilution
#11
Y Tsaturyan, A Barg, E S Polzik, A Schliesser
The small mass and high coherence of nanomechanical resonators render them the ultimate mechanical probe, with applications that range from protein mass spectrometry and magnetic resonance force microscopy to quantum optomechanics. A notorious challenge in these experiments is the thermomechanical noise related to the dissipation through internal or external loss channels. Here we introduce a novel approach to define the nanomechanical modes, which simultaneously provides a strong spatial confinement, full isolation from the substrate and dilution of the resonator material's intrinsic dissipation by five orders of magnitude...
June 12, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28604706/electrical-tuning-of-a-quantum-plasmonic-resonance
#12
Xiaoge Liu, Ju-Hyung Kang, Hongtao Yuan, Junghyun Park, Soo Jin Kim, Yi Cui, Harold Y Hwang, Mark L Brongersma
Surface plasmon (SP) excitations in metals facilitate confinement of light into deep-subwavelength volumes and can induce strong light-matter interaction. Generally, the SP resonances supported by noble metal nanostructures are explained well by classical models, at least until the nanostructure size is decreased to a few nanometres, approaching the Fermi wavelength λF of the electrons. Although there is a long history of reports on quantum size effects in the plasmonic response of nanometre-sized metal particles, systematic experimental studies have been hindered by inhomogeneous broadening in ensemble measurements, as well as imperfect control over size, shape, faceting, surface reconstructions, contamination, charging effects and surface roughness in single-particle measurements...
June 12, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28581510/nanoscale-manipulation-of-membrane-curvature-for-probing-endocytosis-in-live-cells
#13
Wenting Zhao, Lindsey Hanson, Hsin-Ya Lou, Matthew Akamatsu, Praveen D Chowdary, Francesca Santoro, Jessica R Marks, Alexandre Grassart, David G Drubin, Yi Cui, Bianxiao Cui
Clathrin-mediated endocytosis (CME) involves nanoscale bending and inward budding of the plasma membrane, by which cells regulate both the distribution of membrane proteins and the entry of extracellular species. Extensive studies have shown that CME proteins actively modulate the plasma membrane curvature. However, the reciprocal regulation of how the plasma membrane curvature affects the activities of endocytic proteins is much less explored, despite studies suggesting that membrane curvature itself can trigger biochemical reactions...
June 5, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28581509/ultrafast-lithium-diffusion-in-bilayer-graphene
#14
Matthias Kühne, Federico Paolucci, Jelena Popovic, Pavel M Ostrovsky, Joachim Maier, Jurgen H Smet
Solids that simultaneously conduct electrons and ions are key elements for the mass transfer and storage required in battery electrodes. Single-phase materials with a high electronic and high ionic conductivity at room temperature are hard to come by, and therefore multiphase systems with separate ion and electron channels have been put forward instead. Here we report on bilayer graphene as a single-phase mixed conductor that demonstrates Li diffusion faster than in graphite and even surpassing the diffusion of sodium chloride in liquid water...
June 5, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28553962/size-effect-and-scaling-power-law-for-superelasticity-in-shape-memory-alloys-at-the-nanoscale
#15
Jose F Gómez-Cortés, Maria L Nó, Iñaki López-Ferreño, Jesús Hernández-Saz, Sergio I Molina, Andrey Chuvilin, Jose M San Juan
Shape-memory alloys capable of a superelastic stress-induced phase transformation and a high displacement actuation have promise for applications in micro-electromechanical systems for wearable healthcare and flexible electronic technologies. However, some of the fundamental aspects of their nanoscale behaviour remain unclear, including the question of whether the critical stress for the stress-induced martensitic transformation exhibits a size effect similar to that observed in confined plasticity. Here we provide evidence of a strong size effect on the critical stress that induces such a transformation with a threefold increase in the trigger stress in pillars milled on [001] L21 single crystals from a Cu-Al-Ni shape-memory alloy from 2 μm to 260 nm in diameter...
May 29, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28530718/resonant-thermoelectric-nanophotonics
#16
Kelly W Mauser, Seyoon Kim, Slobodan Mitrovic, Dagny Fleischman, Ragip Pala, K C Schwab, Harry A Atwater
Photodetectors are typically based either on photocurrent generation from electron-hole pairs in semiconductor structures or on bolometry for wavelengths that are below bandgap absorption. In both cases, resonant plasmonic and nanophotonic structures have been successfully used to enhance performance. Here, we show subwavelength thermoelectric nanostructures designed for resonant spectrally selective absorption, which creates large localized temperature gradients even with unfocused, spatially uniform illumination to generate a thermoelectric voltage...
May 22, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28530717/sparse-coding-with-memristor-networks
#17
Patrick M Sheridan, Fuxi Cai, Chao Du, Wen Ma, Zhengya Zhang, Wei D Lu
Sparse representation of information provides a powerful means to perform feature extraction on high-dimensional data and is of broad interest for applications in signal processing, computer vision, object recognition and neurobiology. Sparse coding is also believed to be a key mechanism by which biological neural systems can efficiently process a large amount of complex sensory data while consuming very little power. Here, we report the experimental implementation of sparse coding algorithms in a bio-inspired approach using a 32 × 32 crossbar array of analog memristors...
May 22, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28530716/neuromorphic-computation-sparse-codes-from-memristor-grids
#18
Bruno A Olshausen, Christopher J Rozell
No abstract text is available yet for this article.
May 22, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28530715/nanofluidic-device-for-continuous-multiparameter-quality-assurance-of-biologics
#19
Sung Hee Ko, Divya Chandra, Wei Ouyang, Taehong Kwon, Pankaj Karande, Jongyoon Han
Process analytical technology (PAT) is critical for the manufacture of high-quality biologics as it enables continuous, real-time and on-line/at-line monitoring during biomanufacturing processes. The conventional analytical tools currently used have many restrictions to realizing the PAT of current and future biomanufacturing. Here we describe a nanofluidic device for the continuous monitoring of biologics' purity and bioactivity with high sensitivity, resolution and speed. Periodic and angled nanofilter arrays served as the molecular sieve structures to conduct a continuous size-based analysis of biologics...
May 22, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28507334/energy-dependent-path-of-dissipation-in-nanomechanical-resonators
#20
Johannes Güttinger, Adrien Noury, Peter Weber, Axel Martin Eriksson, Camille Lagoin, Joel Moser, Christopher Eichler, Andreas Wallraff, Andreas Isacsson, Adrian Bachtold
Energy decay plays a central role in a wide range of phenomena, such as optical emission, nuclear fission, and dissipation in quantum systems. Energy decay is usually described as a system leaking energy irreversibly into an environmental bath. Here, we report on energy decay measurements in nanomechanical systems based on multilayer graphene that cannot be explained by the paradigm of a system directly coupled to a bath. As the energy of a vibrational mode freely decays, the rate of energy decay changes abruptly to a lower value...
May 15, 2017: Nature Nanotechnology
journal
journal
41445
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"