Model Study on Effect of S=1 Central Spins to Spin Decoherence

We theoretically study mechanisms for decoherence in molecular magnets displaying a clock transition. While it is known that nearby protons are the major source of spin decoherence away from the clock transition, it has been demonstrated that central spins are largely insensitive to nuclei at the clock transition. Although the dominant mechanism for decoherence at the clock transition is unknown, recent experimental data on molecular magnetic crystals indicates that the decoherence time depends on the density of central spins. In this talk, we consider precisely this dependence by simulating a model S = 1 qubit coupled to many other central spin. By changing the magnitude of the dipole interaction between the qubit and other central spins, we effectively simulate the density of central spins in a molecular magnetic crystal.