Because of the wide selectivity of ferromagnetic and ferroelectric(FE)components,electric-field(E-field)control of magnetism via strain mediation can be easily realized through composite multiferroic heterostructures....Because of the wide selectivity of ferromagnetic and ferroelectric(FE)components,electric-field(E-field)control of magnetism via strain mediation can be easily realized through composite multiferroic heterostructures.Here,an MgO-based magnetic tunnel junction(MTJ)is chosen rationally as the ferromagnetic constitution and a high-activity(001)-Pb(Mg_(1/3)Nb_(2/3))_(0.7)Ti_(0.3)O_(3)(PMN-0.3PT)single crystal is selected as the FE component to create a multiferroic MTJ/FE hybrid structure.The shape of tunneling magnetoresistance(TMR)versus in situ E-fields imprints the butterfly loop of the piezo-strain of the FE without magnetic-field bias.The E-field-controlled change in the TMR ratio is up to-0.27%without magnetic-field bias.Moreover,when a typical magnetic field(~±10 Oe)is applied along the minor axis of the MTJ,the butterfly loop is changed significantly by the E-fields relative to that without magnetic-field bias.This suggests that the E-field-controlled junction resistance is spin-dependent and correlated with magnetization switching in the free layer of the MTJ.In addition,based on such a multiferroic heterostructure,a strain-gauge factor up to approximately 40 is achieved,which decreases further with a sign change from positive to negative with increasing magnetic fields.This multiferroic hybrid structure is a promising avenue to control TMR through E-fields in low-power-consumption spintronic and straintronic devices at room temperature.展开更多
Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic devices.Herein,we demonstrate a vertical heterojunction...Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic devices.Herein,we demonstrate a vertical heterojunction made of a correlated electron oxide thin film VO_(2) and a conductive 0.05 wt% Nb-doped TiO_(2) single crystal,whose metal-insulator transition(MIT)across the nanoscale heterointerface can be efficiently modulated by visible light irradiation.The magnitude of the MIT decreases from ~350 in the dark state to ~7 in the illuminated state,obeying a power law with respect to the light power density.The junction resistance is switched in a reversible and synchronous manner by turning light on and off.The optical tunability of it is also exponentially proportional to the light power density,and a 320-fold on/off ratio is achieved with an irradiance of 65.6 mW cm^(-2) below the MIT temperature.While the VO_(2) thin film is metallic above the MIT temperature,the optical tunability is remarkably weakened,with a one-fold change remaining under light illumination.These results are co-attributed to a net reduction(~15 meV)in the apparent barrier height and the photocarrier-injection-induced metallization of the VO_(2) heterointerface through a photovoltaic effect,which is induced by deep defect level transition upon the visible light irradiance at low temperature.Additionally,the optical tunability is minimal,resulting from the quite weak modulation of the already metallic band structure in the Schottky-type junction above the MIT temperature.This work enables a remotely optical scheme to manipulate the MIT,implying potential uncooled photodetection and photoswitch applications.展开更多
Aerobic glycolysis is a hallmark of cancer and is regulated by growth factors,protein kinases and transcription factors.However,it remains poorly understood how these components interact to regulate aerobic glycolysis...Aerobic glycolysis is a hallmark of cancer and is regulated by growth factors,protein kinases and transcription factors.However,it remains poorly understood how these components interact to regulate aerobic glycolysis coordinately.Here,we show that sine oculis homeobox 1(SIX1)phosphorylation integrates growth factors(e.g.TGFβ,EGF)to control aerobic glycolysis and determines its tumor-promoting activity.SIX1 is phosphorylated at serine 225(S225)by growth factors-activated protein kinases ERK1/2 and its phosphorylation is responsible for glycolysis stimulated by some growth factors.SIX1 is dephosphorylated by the atypical protein phosphatase eyes absent 4(EYA4).Phosphorylation blocks non-canonical ubiquitination and degradation of SIX1 through the E3 ubiquitin ligase FZR1.Unexpectedly,the non-canonical phosphorylation mimic SIX1(S225K),but not the canonical phosphorylation mimic SIX1(S225D/E),phenocopies the effects of SIX1 phosphorylation on glycolysis and cancer cell growth and metastasis in vitro and in mice.Compared to normal liver tissues,SIX1 phosphorylation at S225(pS225)is upregulated in human liver cancer tissues.ERK1/2 expression is positively correlated with pS225 and EYA4 expression is negatively associated with pS225 in liver cancer specimens.Moreover,low expression of pS225 had longer disease-free survival and overall survival in patients with liver cancer.Thus,we identify a common mechanism underlying growth factors-mediated glycolysis,and provide a previously unidentified mode for non-classical phosphorylation mimics of a protein.Targeting growth factors/SIX1 signaling pathway may be beneficial to cancer treatment.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52072102 and 11775224)It was also partially funded through the Open Foundation of the Hefei National Laboratory for Physical Sciences at the Microscale(Grant No.KF2020002).
文摘Because of the wide selectivity of ferromagnetic and ferroelectric(FE)components,electric-field(E-field)control of magnetism via strain mediation can be easily realized through composite multiferroic heterostructures.Here,an MgO-based magnetic tunnel junction(MTJ)is chosen rationally as the ferromagnetic constitution and a high-activity(001)-Pb(Mg_(1/3)Nb_(2/3))_(0.7)Ti_(0.3)O_(3)(PMN-0.3PT)single crystal is selected as the FE component to create a multiferroic MTJ/FE hybrid structure.The shape of tunneling magnetoresistance(TMR)versus in situ E-fields imprints the butterfly loop of the piezo-strain of the FE without magnetic-field bias.The E-field-controlled change in the TMR ratio is up to-0.27%without magnetic-field bias.Moreover,when a typical magnetic field(~±10 Oe)is applied along the minor axis of the MTJ,the butterfly loop is changed significantly by the E-fields relative to that without magnetic-field bias.This suggests that the E-field-controlled junction resistance is spin-dependent and correlated with magnetization switching in the free layer of the MTJ.In addition,based on such a multiferroic heterostructure,a strain-gauge factor up to approximately 40 is achieved,which decreases further with a sign change from positive to negative with increasing magnetic fields.This multiferroic hybrid structure is a promising avenue to control TMR through E-fields in low-power-consumption spintronic and straintronic devices at room temperature.
基金supported by the Fundamental Research Funds for the Central Universities(108-4115100092)the National Key Research and Development Program of China(2016YFA0300102 and 2017YFA0205004)+2 种基金the National Natural Science Foundation of China(11775224,11504358,11804324 and 52072102)the Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology(2018CXFX001)the Natural Science Research Projects for the Colleges and Universities of Anhui Province(KJ2018A0660)。
文摘Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic devices.Herein,we demonstrate a vertical heterojunction made of a correlated electron oxide thin film VO_(2) and a conductive 0.05 wt% Nb-doped TiO_(2) single crystal,whose metal-insulator transition(MIT)across the nanoscale heterointerface can be efficiently modulated by visible light irradiation.The magnitude of the MIT decreases from ~350 in the dark state to ~7 in the illuminated state,obeying a power law with respect to the light power density.The junction resistance is switched in a reversible and synchronous manner by turning light on and off.The optical tunability of it is also exponentially proportional to the light power density,and a 320-fold on/off ratio is achieved with an irradiance of 65.6 mW cm^(-2) below the MIT temperature.While the VO_(2) thin film is metallic above the MIT temperature,the optical tunability is remarkably weakened,with a one-fold change remaining under light illumination.These results are co-attributed to a net reduction(~15 meV)in the apparent barrier height and the photocarrier-injection-induced metallization of the VO_(2) heterointerface through a photovoltaic effect,which is induced by deep defect level transition upon the visible light irradiance at low temperature.Additionally,the optical tunability is minimal,resulting from the quite weak modulation of the already metallic band structure in the Schottky-type junction above the MIT temperature.This work enables a remotely optical scheme to manipulate the MIT,implying potential uncooled photodetection and photoswitch applications.
基金supported by the National Natural Science Foundation of China(81930078 and 82330083 to Q.Y.and 81902838 to L.L.)the National Key Research and Development Program of China(2022YFA1104003 to Q.Y.)+2 种基金Natural Science Foundation of Beijing(7204284 to L.L.)Basic and Clinical Collaborative Research Enhanced Program of Anhui Medical University(2021xkjT025 to B.Y.)the Doctoral Start-up Foundation of Anhui Medical University(0110050201 to B.Y.).
文摘Aerobic glycolysis is a hallmark of cancer and is regulated by growth factors,protein kinases and transcription factors.However,it remains poorly understood how these components interact to regulate aerobic glycolysis coordinately.Here,we show that sine oculis homeobox 1(SIX1)phosphorylation integrates growth factors(e.g.TGFβ,EGF)to control aerobic glycolysis and determines its tumor-promoting activity.SIX1 is phosphorylated at serine 225(S225)by growth factors-activated protein kinases ERK1/2 and its phosphorylation is responsible for glycolysis stimulated by some growth factors.SIX1 is dephosphorylated by the atypical protein phosphatase eyes absent 4(EYA4).Phosphorylation blocks non-canonical ubiquitination and degradation of SIX1 through the E3 ubiquitin ligase FZR1.Unexpectedly,the non-canonical phosphorylation mimic SIX1(S225K),but not the canonical phosphorylation mimic SIX1(S225D/E),phenocopies the effects of SIX1 phosphorylation on glycolysis and cancer cell growth and metastasis in vitro and in mice.Compared to normal liver tissues,SIX1 phosphorylation at S225(pS225)is upregulated in human liver cancer tissues.ERK1/2 expression is positively correlated with pS225 and EYA4 expression is negatively associated with pS225 in liver cancer specimens.Moreover,low expression of pS225 had longer disease-free survival and overall survival in patients with liver cancer.Thus,we identify a common mechanism underlying growth factors-mediated glycolysis,and provide a previously unidentified mode for non-classical phosphorylation mimics of a protein.Targeting growth factors/SIX1 signaling pathway may be beneficial to cancer treatment.
