Low-Temperature Series for the Correlation Length in d = 3 Ising Model

We extend low-temperature series for the second moment of the correlation function in d = 3 simple-cubic Ising model from u to u using finite-lattice method, and combining with the series for the susceptibility we obtain the lowtemperature series for the second-moment correlation length to u. An analysis of the obtained series by inhomogeneous differential approximants gives critical exponents 2ν ′ + γ ≈ 2.55 and 2ν ′ ≈ 1.27.