Zero noise extrapolation of transport coefficients

arXiv:2611.05481v1 Announce Type: new Abstract: NISQ devices routinely estimate properties of the noiseless system from measurements at varying noise strengths $\gamma$. These zero-noise extrapolation (ZNE) schemes fail to estimate transport coefficients of conserved quantities when the noise violates the associated conservation laws. We show how to extrapolate measurements in noisy, one-dimensional, non-integrable spin chains to obtain the spin transport coefficients governing linear response in the zero-noise limit. As the wavevector of the Fourier mode of a conserved quantity goes to zero, its decay rate vanishes. The coefficient of the leading momentum dependence defines a transport coefficient in the noiseless system, and an analogous effective coefficient in the noisy one.