Integrability of a quantum derivative nonlinear schroedinger model for spin-1/2 particle

The authors propose a new quantum derivative nonlinear Schroedinger model for spin-1/2 particles. With the help of Lax operator, authors construct the monodromy matrix. It is shown that the monodromy matrix satisfies Yang-Baxter equation. Infinite conserved quantities can be obtained by expanding the monodromy matrix respecting to the spectrum parameter. (author)