Tunnelling current-voltage characteristics of Angstrom gaps measured with terahertz time-domain spectroscopy

Quantum tunnelling becomes inevitable as gap dimensions in metal structures approach the atomic length scale, and light passing through these gaps can be used to examine the quantum processes at optical frequencies. Here, we report on the measurement of the tunnelling current through a 3-Å-wide meta...

Full description

Saved in:
Bibliographic Details
Published in:Scientific reports 2016-06, Vol.6 (1), p.29103-29103, Article 29103
Main Authors: Kim, Joon-Yeon, Kang, Bong Joo, Bahk, Young-Mi, Kim, Yong Seung, Park, Joohyun, Kim, Won Tae, Rhie, Jiyeah, Han, Sanghoon, Jeon, Hyeongtag, Park, Cheol-Hwan, Rotermund, Fabian, Kim, Dai-Sik
Format: Article
Language:English
Subjects:
Electrons
Graphene
Light
Optics
Physics
Quantum dots
Spectrum analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Quantum tunnelling becomes inevitable as gap dimensions in metal structures approach the atomic length scale, and light passing through these gaps can be used to examine the quantum processes at optical frequencies. Here, we report on the measurement of the tunnelling current through a 3-Å-wide metal-graphene-metal gap using terahertz time-domain spectroscopy. By analysing the waveforms of the incident and transmitted terahertz pulses, we obtain the tunnelling resistivity and the time evolution of the induced current and electric fields in the gap and show that the ratio of the applied voltage to the tunnelling current is constant, i.e., the gap shows ohmic behaviour for the strength of the incident electric field up to 30 kV/cm. We further show that our method can be extended and applied to different types of nanogap tunnel junctions using suitable equivalent RLC circuits for the corresponding structures by taking an array of ring-shaped nanoslots as an example.
ISSN:2045-2322
2045-2322
DOI:10.1038/srep29103