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Title: Origin of slow relaxation in the intermediate-disorder regime
Plain: Between the clearly thermal and the apparently localized regimes, disordered chains relax extremely slowly, as power laws in time. What causes this slowness, and whether it ends at a finite time, is unclear.
Precise: In the random-field Heisenberg chain for disorder between about $2J$ and $W_c$, imbalance and spin autocorrelations decay as power laws or subdiffusively over many decades of time. Identify the mechanism (rare Griffiths regions, many-body resonances, or both) and predict the relaxation time $\tau(W, L)$. Answer: a theory predicting $\tau(W)$ and its $L$ dependence, verified by numerics.
Settled by: Agreement between predicted resonance statistics and relaxation times and large-scale time evolution and eigenstate data.
Kind: phenomenon
Answer type: mechanism
References: (empty)
Literature status: open
Status note: (empty)
Posed since: (empty)