Quantum storage in quantum ferromagnets

We must protect inherently fragile quantum data to unlock the potential of technologies. A pertinent concern in schemes for storage is their near-term implementation. Since Heisenberg ferromagnets are readily available, we investigate robust storage. propose use permutation-invariant codes store ferromagnets, because ground space any ferromagnet be symmetric under permutation underlying qubits. By exploiting an area law on expected energy Pauli errors, show that increasing effective dimension can improve lifetime. When maximal, also obtain upper bound error. This result relies perturbation theory, where Davis' divided difference representation Fr\'echet derivatives along with recursive structure these differences. Our numerical bounds allow us better understand how memory lifetimes enhanced ferromagnets.