12-15 July 2011
Saint George Hotel
Africa/Johannesburg timezone

A Quantum Hall Effect without Landau Levels in a Carbon Nanotube.

13 Jul 2011, 14:00
15m
Acro5

Acro5

Oral Presentation Track G - Theoretical and Computational Physics Theoretical

Speaker

Ms Nanette Brand (Stellenbosch University)

Description

The spectrum of a carbon nanotube in a strong enough magnetic field (>50T for a 3nm nanotube) revealed an almost dispersionless band at the Fermi energy. The formation of Landau levels has been theoretically and experimentally investigated. In experimental studies the existence of Landau levels is indirectly derived from longitudinal conductance measurements. We will show that a more direct indication of Landau Levels in the system exists, namely a quantized Hall effect. We present numerical results that show the application of an electric field along the length of the tube lead to a current circulating the circumference and, furthermore, that the conductance is exactly e2/h. This is interesting because the magnetic flux averages to zero around the tube’s circumference. This phenomenon could be explained in terms of the two-dimensional topological theory for the quantum Hall effect even though this system is quasi-one dimensional.

Consider for a student <br> &nbsp; award (Yes / No)? Yes
Level (Hons, MSc, <br> &nbsp; PhD, other)? MSc
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)? No

Primary author

Ms Nanette Brand (Stellenbosch University)

Co-author

Dr Izak Snyman (National Institute of Theoretical Physics)

Presentation Materials

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