Mo S 2 nanoribbon transistor Yanwen Liu Xiang
Mo. S 2 nanoribbon transistor Yanwen Liu, Xiang Yuan, Weiyi Wang, Cheng Zhang and Faxian Xiu* Department of Physics and State Key Laboratory of Surface Physics Fudan University, Shanghai, 200433, China Introduction 2 D mapping of differential conductance Transition Matel dichalcogenides (TMDCs) Ø Layer-by-layer structure Ø Spin-orbit coupling Ø Direct band gap in monolayer Ø Excellent performance of FET B=3 T B=0 T Wang, Q. H. at al Nature nanotechnology 7, 699 -712 (2012). Challenges in TMDCs Ø Choose suitable metal to decrease the Shottky barrier Ø Mobility engineering Ø PN junction Ø Valley physics B=9 T B=6 T Ioffe-Regel criterion Motivation Ø Constrict the width of nanoribbon for band gap engineering The coulomb blockade diamonds split into more diamonds with magnetic fields. As the magnetic field increases, diamonds increase. Differential conductance with different magnetic field Ø Study the ferromagnetic behavior of Mo. S 2 Ø Study the quantum transport of Mo. S 2 nanoribbon Results AFM image of the device As magnetic field increases, the peaks of differential curve shift towards high back gate voltage regime. Differential conductance with different drain source voltage The width of the device is 100 nm. From the AFM image it can tell there is some PMMA residue on the surface of the sample IV curve and 2 D mapping Under small drain source voltage, the device has coulomb blockade behavior and forms some quasi-plateaus. As the drain source voltage increases, the devices has field effect transistor behavior. Conclusion IV curve of nanoribbon device at different back gate voltage. 2 D mapping of differential conductance shows some coulomb blockade diamond overlapped each other. ● Scale down the Mo. S 2 to the width of 100 nm we get some quasi coulomb blockade behavior; ● With magnetic field the coulomb blockade behavior is enhanced; ● However, the coulomb blockade behavior is still not significant enough, the coulomb blockade oscillation is not observed, which means we should keep constricting the width and take the measurement at lower temperature. We gratefully acknowledge the financial support from the department. *To whom correspondence should be addressed: faxian@fudan. edu. cn
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