Hi

 My model doesn't conserve U(1) symmetry. My model is spin chain in transverse magnetic field. if we want to define the Sy we must use complex number i, so can we define complex number in Model.XML file?

Thanks,
Zhian

On Wed, Jan 14, 2009 at 9:54 PM, Matthias Troyer <troyer@phys.ethz.ch> wrote:

Does your model conserve SU(2) or U(1) symmetry? In that case the expectation value is 0. Otherwise you should be able to measure it

Matthias

On 30 Dec 2008, at 04:33, zhian asadzadeh wrote:

Hi Dears

Can i measure the expectation value of the y component of Spin
operator (Sy)?( in DMRG )

Thanks

Zhian