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nicxm
Nov20-08, 11:49 PM
there is a equation for two spins in entangled
Hamiltonian: H=J(\vec{\sigma}^1\cdot\vec{\sigma}^2+\vec{\sigma} ^2\cdot\vec{\sigma}^1)+B(\vec{\sigma}^1_z+\vec{\si gma}^2_z)

where \vec{\sigma}^i=(\sigma^i_x,\sigma^i_y,\sigma^i_z) are the pauli matrics for the ith (i=1,2) spin. J is the exchange constant ,

My difficulties: how can we solve the Hamiltonian to get the four eigenvalues?

thank you for helping me, and i want a detail reprentation.

malawi_glenn
Nov21-08, 12:20 AM
Simply let H act on your four different spin states.

The triplet S_tot = 1, M=+1,0,-1

and the singlet S_tot = 0, M =0

Good luck