[ALPS-users] Sy operator

Dear All,

I am struggling to define the Sy operator in my Hamiltonian. For the 'Spin' hamiltonian the Sx operator is defined as

<SITEOPERATOR name="Sx" site="x"> 1/2*(Splus(x)+Sminus(x)) </SITEOPERATOR>

however when i attempted defining Sy in a similar manner:

<SITEOPERATOR name="Sy" site="x"> 1j/2*(Splus(x)-Sminus(x)) </SITEOPERATOR>

the simulations halt without producing any output. Could you point me how to implement the Sy operator properly and where am i making a mistake?

In the long run I am attempting to apply two different fields in the XY plane, GammaX along x and GammaY along y

Kind regards, Stan