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arXiv · 0712.3767

Spin-orbit interaction and anomalous spin relaxation in carbon nanotube quantum dots

Denis V. Bulaev·Bjoern Trauzettel·Daniel Loss
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Abstract

We study spin relaxation and decoherence caused by electron-lattice and spin-orbit interaction and predict striking effects induced by magnetic fields $B$. For particular values of $B$, destructive interference occurs resulting in ultralong spin relaxation times $T_1$ exceeding tens of seconds. For small phonon frequencies $ω$, we find a $1/\sqrtω$ spin-phonon noise spectrum -- a novel dissipation channel for spins in quantum dots -- which can reduce $T_1$ by many orders of magnitude. We show that nanotubes exhibit zero-field level splitting caused by spin-orbit interaction. This enables an all-electrical and phase-coherent control of spin.

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Denis V. Bulaev, Bjoern Trauzettel, Daniel Loss. 2008-06-04. Spin-orbit interaction and anomalous spin relaxation in carbon nanotube quantum dots. https://doi.org/10.1103/physrevb.77.235301

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