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Ultraslow Growth of Number Entropy in an ℓ-Bit Model of Many-Body Localization
David Aceituno Chávez1, Claudia Artiaco1, Thomas Klein Kvorning1
1Department of Physics, <a href="https://ror.org/026vcq606">KTH Royal Institute of Technology</a>, Stockholm 106 91, Sweden.
Abstract:
We demonstrate that slow growth of the number entropy following a quench from a local product state is consistent with many-body localization. To do this, we construct a novel random circuit ℓ-bit model with exponentially localized ℓ-bits and exponentially decaying interactions between them. We observe an ultraslow growth of the number entropy starting from a Néel state, saturating at a value that grows with system size. This suggests that the observation of such growth in microscopic models is not sufficient to rule out many-body localization.
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