Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Collapse of Charge Gap in Random Mott Insulators   Effects of randomness on interacting fermionic systems in one dimension are
investigated by quantum Monte-Carlo techniques. At first, interacting spinless
fermions are studied whose ground state shows charge ordering. Quantum phase
transition due to randomness is observed associated with the collapse of the
charge ordering. We also treat random Hubbard model focusing on the Mott gap.
Although the randomness closes the Mott gap and low-lying states are created,
which is observed in the charge compressibility, no (quasi-) Fermi surface
singularity is formed. It implies localized nature of the low-lying states.

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The categories of this paper are: stat
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The categories of this paper are: patt-sol
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph