We report the epitaxial growth of high-quality Al_(0.8)Ga_(0.2)Sb/InAs/Al_(0.8)Ga_(0.2)Sb quantum well films characterized by high carrier mobility and strong spin-orbit coupling.By appropriately optimizing the Al-to-...We report the epitaxial growth of high-quality Al_(0.8)Ga_(0.2)Sb/InAs/Al_(0.8)Ga_(0.2)Sb quantum well films characterized by high carrier mobility and strong spin-orbit coupling.By appropriately optimizing the Al-to-Ga ratio in the AlGaSb barrier layer,the quantum confinement of the heterostructure is significantly enhanced.Alongside a giant magnetoresistance ratio of 3.65×10^(5)%,the two-carrier transport model from Hall measurements reveals an ultra-high electron mobility of 7.18×10^(5)cm^(2)·V^(-1)·s^(-1)at low temperatures.Meanwhile,pronounced Shubnikov-de Haas(SdH)quantum oscillations persist up to 30 K,and their single-frequency feature indicates a well-defined Fermi surface without subband mixing in the two-dimensional electron gas channel.Moreover,the large effective g-factor and tilted-field-induced orbital effect lead to the observation of split SdH peaks at large magnetic fields.Our results validate that AlGaSb/InAs quantum well heterostructures are suitable candidates for constructing energy-efficient topological spintronic devices.展开更多
To suppress the resistivity positive temperature coefficient(PTC)effect of ethylene-butyl acrylate copolymer(EBA)-based semi-conductive shielding layer and the injection of charge carriers to insulation layer,the pola...To suppress the resistivity positive temperature coefficient(PTC)effect of ethylene-butyl acrylate copolymer(EBA)-based semi-conductive shielding layer and the injection of charge carriers to insulation layer,the polar molecule maleic anhydride(MAH)is grafted onto EBA macromolecules by melt blending and thermal grafting.The resistivity temperature stability of the grafted semi-conductive composites,as well as the space charge distribution and direct current(DC)breakdown characteristics of cross-linked polyethylene(XLPE)insulation using the composites as the electrode is investigated.The results show that MAH grafting can significantly reduce the volume resistivity of semi-conductive composites,especially at a higher temperature,to suppress the PTC effect.And,the grafted semi-conductive composites can prevent the injection of charge carriers to XLPE insulation from the semi-conductive electrode to improve the space charge distribution and DC breakdown strength of XLPE insulation.The polar anhydride groups in the grafted MAH can enhance the interaction between EBA macromolecular chains and between EBA macromolecular chains and carbon black(CB)to improve the dispersion of CB in EBA matrix and the stability of the internal conductive network at the high temperature,improving the properties of EBA-based semi-conductive shielding layer and DC electrical properties of XLPE insulation layer.展开更多
We present an autonomous physical vapor deposition system that integrates hardware automation,in-situ optical spectroscopy,and Bayesian machine learning into a complete self-driving laboratory framework making decisio...We present an autonomous physical vapor deposition system that integrates hardware automation,in-situ optical spectroscopy,and Bayesian machine learning into a complete self-driving laboratory framework making decisions on the fly.Using silver thin films as a model material,our platform efficiently navigates acomplex parameter space through active learning.By introducing a thin physical layer denoted as calibration layer,the machine learning models adapt to sample-specific conditions on the fly and reliably predict the deposition conditions to achieve user-specified optical properties.Moreover,from the high-throughput experimental data,the algorithm systematically captures the complex parameter-property relationships that are challenging to deduce by conventional trial-anderror methods.This study demonstrates the potential of self-driving laboratories for both reducing human labor and gaining new understanding of materials,providing a streamlined approach to enable self-driving physical vapor deposition systems.展开更多
Transdermal drug delivery(TDD)systems have evolved,with skin electronics emerging as a technology capable of enabling efficient drug administration.However,conventional skin electronics often rely on rigid materials a...Transdermal drug delivery(TDD)systems have evolved,with skin electronics emerging as a technology capable of enabling efficient drug administration.However,conventional skin electronics often rely on rigid materials and expensive fabrication processes,limiting flexibility and skin-adhesion.In this study,we developed cellulose nanofiber(CNFs)-based adhesive electronics by integrating a three-dimensional octopus-inspired architecture(OIA)and a conductive layer.The OIA imprinted on CNFs enhanced adhesion by leveraging the synergistic effect of its adhesive structure and the ability to remain stable even after absorbing active ingredient solutions.Unlike conventional fiber-based TDD platforms,the optimized CNFs-OIA retains its architecture,enabling suction-based adhesion to improve skin attachment.To further enhance the TDD efficiency,we integrated a conductive layer into the CNFs-OIA.This conductive interface generates microcurrents that reduce the electrical resistance of the stratum corneum and facilitates the ionization of active ingredients,thereby improving skin penetration.展开更多
基金supported by R&D the National Key Program of China(Grant No.2021YFA0715503)the Major Project ofShanghai Municipal Science and Technology(Grant No.2018SHZDZX02)the ShanghaiTech Mate rial Device and Soft Matter Nano-fabrication Labs(No.SMN180827).
文摘We report the epitaxial growth of high-quality Al_(0.8)Ga_(0.2)Sb/InAs/Al_(0.8)Ga_(0.2)Sb quantum well films characterized by high carrier mobility and strong spin-orbit coupling.By appropriately optimizing the Al-to-Ga ratio in the AlGaSb barrier layer,the quantum confinement of the heterostructure is significantly enhanced.Alongside a giant magnetoresistance ratio of 3.65×10^(5)%,the two-carrier transport model from Hall measurements reveals an ultra-high electron mobility of 7.18×10^(5)cm^(2)·V^(-1)·s^(-1)at low temperatures.Meanwhile,pronounced Shubnikov-de Haas(SdH)quantum oscillations persist up to 30 K,and their single-frequency feature indicates a well-defined Fermi surface without subband mixing in the two-dimensional electron gas channel.Moreover,the large effective g-factor and tilted-field-induced orbital effect lead to the observation of split SdH peaks at large magnetic fields.Our results validate that AlGaSb/InAs quantum well heterostructures are suitable candidates for constructing energy-efficient topological spintronic devices.
基金National Natural Science Foundation of China,Grant/Award Number:U20A20307Key Laboratory of Engineering Dielectrics and Its Application(Harbin University of Science and Technology),Ministry of Education,Grant/Award Number:KFM202102。
文摘To suppress the resistivity positive temperature coefficient(PTC)effect of ethylene-butyl acrylate copolymer(EBA)-based semi-conductive shielding layer and the injection of charge carriers to insulation layer,the polar molecule maleic anhydride(MAH)is grafted onto EBA macromolecules by melt blending and thermal grafting.The resistivity temperature stability of the grafted semi-conductive composites,as well as the space charge distribution and direct current(DC)breakdown characteristics of cross-linked polyethylene(XLPE)insulation using the composites as the electrode is investigated.The results show that MAH grafting can significantly reduce the volume resistivity of semi-conductive composites,especially at a higher temperature,to suppress the PTC effect.And,the grafted semi-conductive composites can prevent the injection of charge carriers to XLPE insulation from the semi-conductive electrode to improve the space charge distribution and DC breakdown strength of XLPE insulation.The polar anhydride groups in the grafted MAH can enhance the interaction between EBA macromolecular chains and between EBA macromolecular chains and carbon black(CB)to improve the dispersion of CB in EBA matrix and the stability of the internal conductive network at the high temperature,improving the properties of EBA-based semi-conductive shielding layer and DC electrical properties of XLPE insulation layer.
基金supported by University of Chicago Big Idea Generator Seed Grantwith additional hardware support by the National Science Foundation(NSF CNS-2019131)+2 种基金Collaboration between the Yang and Chen groups was also supported by the National Science Foundation(NSF ECCS-2427944)This work made use of the shared facilities at the University of Chicago Materials Research Science and Engineering Center,supported by National Science Foundation under award number DMR-2011854This work made use of the Pritzker Nanofabrication Facility at the Pritzker School of Molecular Engineering at the University of Chicago,which receives support from Soft and Hybrid Nanotechnology Experimental(SHyNE)Resource(NSF ECCS-2025633),a node of the National Science Foundation’s National Nanotechnology Coordinated Infrastructure.
文摘We present an autonomous physical vapor deposition system that integrates hardware automation,in-situ optical spectroscopy,and Bayesian machine learning into a complete self-driving laboratory framework making decisions on the fly.Using silver thin films as a model material,our platform efficiently navigates acomplex parameter space through active learning.By introducing a thin physical layer denoted as calibration layer,the machine learning models adapt to sample-specific conditions on the fly and reliably predict the deposition conditions to achieve user-specified optical properties.Moreover,from the high-throughput experimental data,the algorithm systematically captures the complex parameter-property relationships that are challenging to deduce by conventional trial-anderror methods.This study demonstrates the potential of self-driving laboratories for both reducing human labor and gaining new understanding of materials,providing a streamlined approach to enable self-driving physical vapor deposition systems.
基金support from the National Research Foundation of Korea(RS-2024-00352352)the Market-led K-sensor technology program(RS-2022-00154781,Development of large-area wafer-level flexible/stretchable hybrid sensor platform technology for form factor-free highly integrated convergence sensor),funded By the Ministry of Trade,Industry&Energy(MOTIE,Korea)+1 种基金support of the industry-academia cooperation research of Mimetics Co.,Ltdsupported by theSungKyunKwanUniversity and the BK21 FOUR(Graduate School Innovation)funded by the Ministry of Education(MOE,Korea)and National Research Foundation of Korea(NRF)。
文摘Transdermal drug delivery(TDD)systems have evolved,with skin electronics emerging as a technology capable of enabling efficient drug administration.However,conventional skin electronics often rely on rigid materials and expensive fabrication processes,limiting flexibility and skin-adhesion.In this study,we developed cellulose nanofiber(CNFs)-based adhesive electronics by integrating a three-dimensional octopus-inspired architecture(OIA)and a conductive layer.The OIA imprinted on CNFs enhanced adhesion by leveraging the synergistic effect of its adhesive structure and the ability to remain stable even after absorbing active ingredient solutions.Unlike conventional fiber-based TDD platforms,the optimized CNFs-OIA retains its architecture,enabling suction-based adhesion to improve skin attachment.To further enhance the TDD efficiency,we integrated a conductive layer into the CNFs-OIA.This conductive interface generates microcurrents that reduce the electrical resistance of the stratum corneum and facilitates the ionization of active ingredients,thereby improving skin penetration.
