Pauli spin blockade in carbon nanotube double quantum dots

We report Pauli spin blockade in a carbon nanotube double quantum dot defined by tunnel barriers at the contacts and a structural defect in the nanotube. We observe a pronounced current suppression for negative source-drain bias voltages, which is investigated for both symmetric and asymmetric coupl...

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Bibliographic Details
Main Authors: Buitelaar, MR, Fransson, J, Cantone, A, Smith, C, Anderson, D, Jones, G, Ardavan, A, Khlobystov, A, Watt, A, Porfyrakis, K, Briggs, G
Format: Journal article
Language:English
Published: 2008
Description
Summary:We report Pauli spin blockade in a carbon nanotube double quantum dot defined by tunnel barriers at the contacts and a structural defect in the nanotube. We observe a pronounced current suppression for negative source-drain bias voltages, which is investigated for both symmetric and asymmetric coupling of the quantum dots to the leads. The measured differential conductance agrees well with a theoretical model of a double quantum dot system in the spin-blockade regime, which allows us to estimate the occupation probabilities of the relevant singlet and triplet states. This work shows that effective spin-to-charge conversion in nanotube quantum dots is feasible and opens the possibility of single-spin readout in a material that is not limited by hyperfine interaction with nuclear spins. © 2008 The American Physical Society.