Relaxation and Dephasing in a Two-electron 13C Nanotube Double Quantum   Dot
  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. 
H. O. H. Churchill, F. Kuemmeth, J. W. Harlow, A. J. Bestwick, E. I.   Rashba, K. Flensberg, C. H. Stwertka, T. Taychatanapa...