MATRIX PRODUCT EIGENSTATES FOR ONE-DIMENSIONAL STOCHASTIC-MODELS AND QUANTUM SPIN CHAINS

We show that all zero-energy eigenstates of an arbitrary m-state quant um spin chain Hamiltonian with nearest-neighbour interaction in the bu lk and single site boundary terms, which can also describe the dynamic s of stochastic models, can be written as matrix product states. This means that the weights in these states can be expressed as expectation values in a Fock representation of an algebra generated by 2m operato rs fulfilling m(2) quadratic relations which are defined by the Hamilt onian.