Magnetoconductance of carbon nanotubes probed in parallel magnetic fields up to 60 T

Abstract

Magnetoconductance of carbon nanotubes (CNTs) is investigated. We clearly show that a semiconducting CNT can be converted into a metallic one, or vice versa, with the application of a large magnetic field parallel to the tube axis, providing a consistent confirmation of the Aharonov-Bohm (AB) effect on the band structure of CNTs. We also demonstrate that magneticfield values where the semiconductor-to-metal transition occurs can be tuned by mechanical strain. Combined control of both the strain and the AB effect may open up new possibilities for CNT devices. In addition, we propose an idea to manipulate spin-split subbands of CNTs, resulting from spin-orbit interaction (SOI), by using the magnetic field to generate sizeable spin-polarized currents. 2.0

Spin filtering and entanglement detection due to spin-orbit interaction in carbon nanotube cross-junctions

“…This use of the cross-junction as a versatile spin filter at high efficiency complements a previous suggestion of exploring bound states in SOI-split CNTs for perfect spin filtering. 34,72 It also complements the alternative of SOI induced spin-filtering in CNT quantum dot setups. 41 …”