We report the successful growth of the tetragonal FeS film with one or two unit-cell (UC) thickness on SrTiO33(001) substrates by molecular beam epitaxy. Large lattice constant mismatch with the substrate leads to...We report the successful growth of the tetragonal FeS film with one or two unit-cell (UC) thickness on SrTiO33(001) substrates by molecular beam epitaxy. Large lattice constant mismatch with the substrate leads to high density of defects in single-UC FeS, while it has been significantly reduced in the double-UC thick film due to the lattice relaxation. The scanning tunneling spectra on the surface of the FeS thin film reveal the electronic doping effect of single-UC FeS from the substrate. In addition, at the Fermi level, the energy gaps of approximately 1.5?meV are observed in the films of both thicknesses at 4.6?K and below. The absence of coherence peaks of gap spectra may be related to the preformed Cooper-pairs without phase coherence.展开更多
Layered material indium selenide(InxSey)is a promising candidate for building next-generation electronic and photonic devices.We report a zirconium aided MBE growth of this van der Waals material.When co-depositing zi...Layered material indium selenide(InxSey)is a promising candidate for building next-generation electronic and photonic devices.We report a zirconium aided MBE growth of this van der Waals material.When co-depositing zirconium and selenium onto an indium phosphide substrate with a substrate temperature of 400℃at a constant zirconium flux rate of 0.01 ML/min,the polymorphic Inx Sey layer emerges on top of the insulating ZrSe2 layer.Different archetypes,such as InSe,α-In2Se3 and α-In2Se3,are found in the InxSey layers.A negative magnetoresistance of 40%at 2 K under 9 T magnetic field is observed.Such an InxSeyZrSe2 heterostructure with good lattice-matching may serve as a candidate for device applications.展开更多
基金Supported by the National Natural Science Foundation of Chinathe Ministry of Science and Technology of Chinathe Specialized Research Fund for the Doctoral Program of Higher Education under Grant No 20130002120033
文摘We report the successful growth of the tetragonal FeS film with one or two unit-cell (UC) thickness on SrTiO33(001) substrates by molecular beam epitaxy. Large lattice constant mismatch with the substrate leads to high density of defects in single-UC FeS, while it has been significantly reduced in the double-UC thick film due to the lattice relaxation. The scanning tunneling spectra on the surface of the FeS thin film reveal the electronic doping effect of single-UC FeS from the substrate. In addition, at the Fermi level, the energy gaps of approximately 1.5?meV are observed in the films of both thicknesses at 4.6?K and below. The absence of coherence peaks of gap spectra may be related to the preformed Cooper-pairs without phase coherence.
基金Supported by the National Natural Science Foundation of China(Grant No.11874233).
文摘Layered material indium selenide(InxSey)is a promising candidate for building next-generation electronic and photonic devices.We report a zirconium aided MBE growth of this van der Waals material.When co-depositing zirconium and selenium onto an indium phosphide substrate with a substrate temperature of 400℃at a constant zirconium flux rate of 0.01 ML/min,the polymorphic Inx Sey layer emerges on top of the insulating ZrSe2 layer.Different archetypes,such as InSe,α-In2Se3 and α-In2Se3,are found in the InxSey layers.A negative magnetoresistance of 40%at 2 K under 9 T magnetic field is observed.Such an InxSeyZrSe2 heterostructure with good lattice-matching may serve as a candidate for device applications.