The efficient near-infrared light detection of the MoTe2/germanium(Ge)heterojunction has been demonstrated.The fabricated MoTe2/Ge van der Waals heterojunction shows excellent photoresponse performances under the illu...The efficient near-infrared light detection of the MoTe2/germanium(Ge)heterojunction has been demonstrated.The fabricated MoTe2/Ge van der Waals heterojunction shows excellent photoresponse performances under the illumination of a 915 nm laser.The photoresponsivity and specific detectivity can reach to 12,460 A/W and 3.3×10^12 Jones,respectively.And the photoresponse time is 5 ms.However,the MoTe2/Ge heterojunction suffers from a large reverse current at dark due to the low barrier between MoTe2 and Ge.Therefore,to reduce the reverse current,an ultrathin GeO2 layer deposited by ozone oxidation has been introduced to the MoTe2/Ge heterojunction.The reverse current of the MoTe2/GeO2/Ge heterojunction at dark was suppressed from 0.44µA/µm^2 to 0.03 nA/µm^2,being reduced by more than four orders of magnitude.The MoTe2/Ge heterojunction with the GeO2 layer also exhibits good photoresponse performances,with a high responsivity of 15.6 A/W,short response time of 5 ms,and good specific detectivity of 4.86×10^11 Jones.These properties suggest that MoTe2/Ge heterostructure is one of the promising structures for the development of high performance near-infrared photodetectors.展开更多
In this work,we have fabricated a single layer graphene spin transistor on SiO2/Si with a semiconducting tri-layer MoS2 as the tunneling barrier between the ferromagnetic electrodes and the graphene channel.The spin t...In this work,we have fabricated a single layer graphene spin transistor on SiO2/Si with a semiconducting tri-layer MoS2 as the tunneling barrier between the ferromagnetic electrodes and the graphene channel.The spin transport in this parallel heterostructure were investigated in detail.The spin switch signal was controlled by tuning the conductivity of MoS2 with different gate voltages.When MoS2 was turned off under negative back gate voltage,the spin switch signal was clearly obtained,whereas it disappeared when MoS2 was conductive under positive back gate bias.This spin transistor showed on,subthreshold and off states when back gate voltage changed from negative to positive.This work exploited a new possibility of semiconducting 2D materials as the tunneling barrier of spin valves.展开更多
基金supported by the National Key Research and Development Program of China(Nos.2016YFA0200400 and 2016YFA0302300)the National Science and Technology Major Project of China(No.2016ZX02301001).
文摘The efficient near-infrared light detection of the MoTe2/germanium(Ge)heterojunction has been demonstrated.The fabricated MoTe2/Ge van der Waals heterojunction shows excellent photoresponse performances under the illumination of a 915 nm laser.The photoresponsivity and specific detectivity can reach to 12,460 A/W and 3.3×10^12 Jones,respectively.And the photoresponse time is 5 ms.However,the MoTe2/Ge heterojunction suffers from a large reverse current at dark due to the low barrier between MoTe2 and Ge.Therefore,to reduce the reverse current,an ultrathin GeO2 layer deposited by ozone oxidation has been introduced to the MoTe2/Ge heterojunction.The reverse current of the MoTe2/GeO2/Ge heterojunction at dark was suppressed from 0.44µA/µm^2 to 0.03 nA/µm^2,being reduced by more than four orders of magnitude.The MoTe2/Ge heterojunction with the GeO2 layer also exhibits good photoresponse performances,with a high responsivity of 15.6 A/W,short response time of 5 ms,and good specific detectivity of 4.86×10^11 Jones.These properties suggest that MoTe2/Ge heterostructure is one of the promising structures for the development of high performance near-infrared photodetectors.
基金This work was supported by the National Key Research and Development Program of China under Grant 2016YFA0200400 and Grant 2016YFA0302300the National Science and Technology Major Project of China under Grant 2016ZX02301001.S.Zhang would like to thank for the financial support by China Scholarship Council.In addition,she appreciated the help from Prof.Barbaras Ozyilmaz and Dr.Jiawei Liu in National University of Singapore,and the experiment was also supported by Graphene Research Centre in National University of Singapore.
文摘In this work,we have fabricated a single layer graphene spin transistor on SiO2/Si with a semiconducting tri-layer MoS2 as the tunneling barrier between the ferromagnetic electrodes and the graphene channel.The spin transport in this parallel heterostructure were investigated in detail.The spin switch signal was controlled by tuning the conductivity of MoS2 with different gate voltages.When MoS2 was turned off under negative back gate voltage,the spin switch signal was clearly obtained,whereas it disappeared when MoS2 was conductive under positive back gate bias.This spin transistor showed on,subthreshold and off states when back gate voltage changed from negative to positive.This work exploited a new possibility of semiconducting 2D materials as the tunneling barrier of spin valves.
