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arXiv · 0811.3239

Relaxation and Dephasing in a Two-electron 13C Nanotube Double Quantum Dot

H. O. H. Churchill·F. Kuemmeth·J. W. Harlow·A. J. Bestwick·E. I. Rashba·K. Flensberg·C. H. Stwertka·T. Taychatanapat·S. K. Watson·C. M. Marcus
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Abstract

We use charge sensing of Pauli blockade (including spin and isospin) in a two-electron 13C nanotube double quantum dot to measure relaxation and dephasing times. The relaxation time, T1, first decreases with parallel magnetic field then goes through a minimum in a field of 1.4 T. We attribute both results to the spin-orbit-modified electronic spectrum of carbon nanotubes, which suppresses hyperfine mediated relaxation and enhances relaxation due to soft phonons. The inhomogeneous dephasing time, T2*, is consistent with previous data on hyperfine coupling strength in 13C nanotubes.

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H. O. H. Churchill, F. Kuemmeth, J. W. Harlow, A. J. Bestwick, E. I. Rashba, K. Flensberg, C. H. Stwertka, T. Taychatanapat, S. K. Watson, C. M. Marcus. 2008-11-19. Relaxation and Dephasing in a Two-electron 13C Nanotube Double Quantum Dot. https://doi.org/10.1103/physrevlett.102.166802

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