Matrix H in Subspace 30 with Dimension 4
H is the Hamiltonian. Here we set µ=0. For grand-canonical calculations add -6µ to the main diagonal.
-2*h
0
0
-2*Sqrt[2]*t
0
-2*h + U
-2*Sqrt[2]*t
0
0
-2*Sqrt[2]*t
-2*h + U
-2*t
-2*Sqrt[2]*t
0
-2*t
-2*h + U