Abstract
Arecentlyintroducedone-dimensionalthree-orbitalHubbardmodeldisplaysorbital-selectiveMottphaseswithexoticspinarrangementssuchasspinblockstates[J.Rinc´onetal.,Phys.Rev.Lett.112,106405(2014)].Inthispublicationweshowthattheconstrained-pathquantumMonteCarlo(CPQMC)techniquecanaccuratelyreproducethephasediagramofthismultiorbitalone-dimensionalmodel,pavingthewaytofutureCPQMCstudiesinsystemswithmorechallenginggeometries,suchasladdersandplanes.ThesuccessofthisapproachreliesonusingtheHartree-FocktechniquetopreparethetrialstatesneededinCPQMC.Wealsostudyasimplifiedversionofthemodelwherethepair-hoppingtermisneglectedandtheHundcouplingisrestrictedtoitsIsingcomponent.Thecorrespondingphasediagramsareshowntobeonlymildlya ectedbytheabsenceofthesetechnicallydiÿcult-to-implementterms.ThisisconfirmedbyadditionalDensityMatrixRenormalizationGroupandDeterminantQuantumMonteCarlocalculationscarriedoutforthesamesimplifiedmodel,withthelatterdisplayingonlymildFermionsignproblems.Weconcludethatthesemethodsareabletocapturequantitativelytherichphysicsoftheseveralorbital-selectiveMottphases(OSMP)displayedbythismodel,thusenablingcomputationalstudiesoftheOSMPregimeinhigherdimensions,beyondstaticordynamicmeanfieldapproximations.
