FermionSiteU0.h

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#ifndef FERMIONSITEU0_H_
#define FERMIONSITEU0_H_
 
#include "DmrgTypedefs.h"
 
#include "symmetry/S1xS2.h"
#include "symmetry/SU2.h"
#include "symmetry/U1.h"
 
#include "tensors/SiteOperatorQ.h"
 
template <typename Symmetry> class FermionSite;
 
// template <>
// class FermionSite<Sym::U0>
// {
//  typedef double Scalar;
//  typedef Sym::U0 Symmetry;
//  typedef SiteOperatorQ<Symmetry,Eigen::Matrix<Scalar,Eigen::Dynamic,Eigen::Dynamic> > OperatorType;
// public:
//  FermionSite() {};
//  FermionSite(bool U_IS_INFINITE, bool UPH_IS_INFINITE);
    
//  OperatorType Id_1s() const {return Id_1s_;}
//  OperatorType F_1s() const {return F_1s_;}
    
//  OperatorType c_1s(SPIN_INDEX sigma) const { if (sigma == UP) {return cup_1s_;} return cdn_1s_;}
//  OperatorType cdag_1s(SPIN_INDEX sigma) const { if (sigma == UP) {return cup_1s_.adjoint();} return cdn_1s_.adjoint();}
 
//  OperatorType n_1s() const {return n_1s(UP) + n_1s(DN);}
//  OperatorType n_1s(SPIN_INDEX sigma) const { if (sigma == UP) {return nup_1s_;} return ndn_1s_;}
//  OperatorType ns_1s() const {return n_1s() - 2.*d_1s();}
//  OperatorType nh_1s() const {return 2.*d_1s() - n_1s() + Id_1s();}
//  OperatorType d_1s() const {return d_1s_;}
 
//  OperatorType Sz_1s() const {return Sz_1s_;}
//  OperatorType Sp_1s() const {return Sp_1s_;}
//  OperatorType Sm_1s() const {return Sm_1s_;}
 
//  OperatorType Tz_1s() const {return 0.5*(n_1s() - Id_1s());}
//  OperatorType cc_1s() const {return cc_1s_;}
//  OperatorType cdagcdag_1s() const {return cdagcdag_1s_;}
 
//  Qbasis<Symmetry> basis_1s() const {return basis_1s_;}
// protected:
    
//  Qbasis<Symmetry> basis_1s_;
 
//  OperatorType Id_1s_; //identity
//  OperatorType F_1s_; //Fermionic sign
//  OperatorType cup_1s_; //annihilation
//  OperatorType cdn_1s_; //annihilation
    
//  OperatorType n_1s_; //particle number
//  OperatorType nup_1s_; //particle number
//  OperatorType ndn_1s_; //particle number
//  OperatorType d_1s_; //double occupancy
 
//  OperatorType Sz_1s_; //orbital spin
//  OperatorType Sp_1s_; //orbital spin
//  OperatorType Sm_1s_; //orbital spin
    
//  OperatorType Tz_1s_; //orbital pseude spin
//  OperatorType cc_1s_; //pairing
//  OperatorType cdagcdag_1s_; //pairing adjoint
// };
 
// FermionSite<Sym::U0>::
// FermionSite(bool U_IS_INFINITE, bool UPH_IS_INFINITE)
// {
 
//  //create basis for one Fermionic Site
//  typename Symmetry::qType Q = {}; //empty and doubly occupied state
//  Eigen::Index inner_dim;
//  std::vector<std::string> ident;
    
//  if (!UPH_IS_INFINITE and U_IS_INFINITE)
//  {
//      ident.push_back("empty");
//      ident.push_back("up");
//      ident.push_back("dn");
//      inner_dim = 3;
//      basis_1s_.push_back(Q,inner_dim,ident);
//      ident.clear();
//  }
//  else if (!U_IS_INFINITE and !UPH_IS_INFINITE)
//  {
//      ident.push_back("empty");
//      ident.push_back("up");
//      ident.push_back("dn");
//      ident.push_back("double");
//      inner_dim = 4;
//      basis_1s_.push_back(Q,inner_dim,ident);
//      ident.clear();
//  }
//  else
//  {
//      ident.push_back("up");
//      ident.push_back("dn");
//      inner_dim = 2;
//      basis_1s_.push_back(Q,inner_dim,ident);
//      ident.clear();      
//  }
    
//  Id_1s_  = OperatorType({},basis_1s_);
//  F_1s_   = OperatorType({},basis_1s_);
//  cup_1s_ = OperatorType({},basis_1s_);
//  cdn_1s_ = OperatorType({},basis_1s_);
//  d_1s_   =  OperatorType({},basis_1s_);
//  Sz_1s_  = OperatorType({},basis_1s_);
//  Sp_1s_  = OperatorType({},basis_1s_);
//  Sm_1s_  = OperatorType({},basis_1s_);
    
//  // create operators one orbitals    
//  if (!UPH_IS_INFINITE) Id_1s_("empty", "empty") = 1.;
    
//  if (!U_IS_INFINITE and !UPH_IS_INFINITE) Id_1s_("double", "double") = 1.;
//  Id_1s_("up", "up") = 1.;
//  Id_1s_("dn", "dn") = 1.;
    
//  if (!UPH_IS_INFINITE) F_1s_("empty", "empty") = 1.;
//  if (!U_IS_INFINITE and !UPH_IS_INFINITE) F_1s_("double", "double") = 1.;
//  F_1s_("up", "up") = -1.;
//  F_1s_("dn", "dn") = -1.;
    
//  if (!UPH_IS_INFINITE) cup_1s_("empty", "up")  = 1.;
//  if (!U_IS_INFINITE and !UPH_IS_INFINITE) cup_1s_("dn", "double") = 1.;
 
//  if (!UPH_IS_INFINITE) cdn_1s_("empty", "dn")  = 1.;
//  if (!U_IS_INFINITE and !UPH_IS_INFINITE) cdn_1s_("up", "double") = -1.;
    
//  nup_1s_ = cup_1s_.adjoint() * cup_1s_;
//  ndn_1s_ = cdn_1s_.adjoint() * cdn_1s_;
//  if (!U_IS_INFINITE and !UPH_IS_INFINITE) d_1s_( "double", "double" ) = 1.;
    
//  Sz_1s_ = 0.5*(nup_1s_ - ndn_1s_);
//  Sp_1s_ = cup_1s_.adjoint() * cdn_1s_;
//  Sm_1s_ = Sp_1s_.adjoint();
//  cc_1s_ = cdn_1s_ * cup_1s_; //The sign convention corresponds to c_DN c_UP
//  cdagcdag_1s_ = cc_1s_.adjoint(); //The sign convention corresponds to (c_DN c_UP)†=c_UP† c_DN†
 
// }
 
#endif //FERMIONSITEU0_H_