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Production of minimally entangled typical thermal states with the Krylov-space approach

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 نشر من قبل Gonzalo Alvarez
 تاريخ النشر 2013
  مجال البحث فيزياء
والبحث باللغة English
 تأليف G. Alvarez




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The minimally entangled typical thermal states algorithm is applied to fermionic systems using the Krylov-space approach to evolve the system in imaginary time. The convergence of local observables is studied in a tight-binding system with a site-dependent potential. The temperature dependence of the superconducting correlations of the attractive Hubbard model is analyzed on chains, showing an exponential decay with distance and exponents proportional to the temperature at low temperatures, as expected. In addition, the non-local parity correlator is calculated at finite temperature. Other possible applications of the minimally entangled typical thermal states algorithm to fermionic systems are also discussed.



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