1 / 17

Tunneling between helical edge states through extended contacts

NANO-CTM Meeting. Cargese , 25 October 2012. Tunneling between helical edge states through extended contacts. Giacomo Dolcetto. Università degli Studi di Genova, Physics Department. In collaboration with …. Quantum transport and nanodevices.

onslow
Download Presentation

Tunneling between helical edge states through extended contacts

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. NANO-CTM Meeting Cargese, 25 October 2012 Tunnelingbetweenhelicaledgestatesthroughextendedcontacts Giacomo Dolcetto Università degli Studi di Genova, PhysicsDepartment

  2. In collaborationwith … Quantum transport and nanodevices Nicodemo Magnoli, Maura Sassetti, Dario Ferraro and Simone Barbarino

  3. Outline • Two-dimensionaltopologicalinsulators CdTe • Helicaledgestates HgTe CdTe • Tunneling in QPC geometry • Tunnelingthroughextendedcontacts

  4. Two-dimensionaltopologicalinsulators [B. A. Bernevig, T. L. Hughes, and S.-C. Zhang, Science 314, 1757 (2006)] CdTe CdTe HgTe HgTe CdTe CdTe Insulating bulk states VS conductingedgestates Spin and momentum are lockedintoeachother [L. Qi and S.-C.Zhang, Rev. Mod. Phys. 83, 1057 (2011)]

  5. Quantum spin Hall effect [C. L. Kane and E. J. Mele, Phys. Rev. Lett. 95, 146802 (2005)] [M. Königet al., Science 318, 766 (2007)]

  6. HelicalLuttingerliquid [C. Wu, B. A. Bernevig, S. –C. Zhang, PRL 96, 106401 (2006)] Quantum wire QHE QSHE Spinfull LL Chiral LL Helical LL Bosonization: Uniquecollectiveexcitationspropagationvelocity

  7. Tunnelingthrough QPC [A. Strom, H. Johannesson, PRL 102, 096806 (2009)] Interaction-dependendentpower-laws

  8. Tunnelingthroughextendedcontacts [G. D., S. Barbarino, D. Ferraro, N. Magnoli, M. Sassetti, PRB 95, 195138 (2012)] The modulatingfunctiondepends on bias and temperature, thusmodifying QPC behaviours

  9. Tunnelingthroughextendedcontacts [G. D., S. Barbarino, D. Ferraro, N. Magnoli, M. Sassetti, PRB 95, 195138 (2012)] Tunnelingconductanceshows a uniquepeakforaninteractiondependentbiasvoltagevalue Information aboutinteractionstrength Measuramentof the peak no spin-chargeseparation in helical LL butclose connection between spin and momentum Uniquepeak

  10. Summary • Helicaledgestates in QSHE are carachterized by close connection between spin and chirality • Tunnelingproperties are useful in order to study the properties of the helicaledgestates • Extended tunnelingcontactsmayconfirm the helicity of the edgestates, and allow to extractinformationsaboutinteractions Thankyouforyourattention!

  11. NANO-CTM Meeting Cargese, 25 October 2012 Tunnelingbetweenhelicaledgestatesthroughextendedcontacts Giacomo Dolcetto Università degli Studi di Genova, PhysicsDepartment

  12. Finite temperature effects

  13. New power-lawsbehaviors

  14. Otherusefulplots… Varying the lengthof the contact Varying the interaction Varying the length of the contact Varying the interaction

  15. Otherusefulplots… Varying the temperature Varying the interaction Varying the lengthof the contact

  16. Otherusefulplots… Varying the temperature Varying the interaction Varying the lengthof the contact

More Related