Exact solution of the one-dimensional Hubbard model with arbitrary boundary magnetic fields

Understand

The one-dimensional Hubbard model with arbitrary boundary magnetic fields is solved exactly via the Bethe ansatz methods.

• With the coordinate Bethe ansatz in the charge sector, the second eigenvalue problem associated with the spin sector is constructed.
• It is shown that the second eigenvalue problem can be transformed into that of the inhomogeneous XXX spin chain with arbitrary boundary fields which can be solved via the off-diagonal Bethe ansatz method.