Distillability sudden death in qutrit-qutrit systems under global and multilocal dephasing

Recently Song et al. [Phys. Rev. A 80, 012331 (2009)] discovered that certain two-qutrit entangled states interacting with multilocal dephasing undergo distillability sudden death (DSD). We generalized their studies for quantum states under global, collective, and multilocal dephasing. We found that for a specific family of quantum states DSD and entanglement sudden death may happen under global dephasing as well as under multilocal dephasing. Moreover, for these states simple local unitary transformations may not avoid DSD under the current dynamics. As there is no definitive criterion for separability or entanglement of density matrices with dimensions greater than six, therefore we believe that the results obtained in this article are restricted to the specific family of states considered here.