SIN and SIS tunneling in cuprates

Abstract

We calculate the SIN and SIS tunneling conductances for the spin-fermion model. We argue that at strong spin-fermion coupling, relevant to cuprates, both conductances have dip features near the threshold frequencies when a tunneling electron begin emitting propagating spin excitation. We argue that the resonance spin frequency measured in neutron scattering can be inferred from the tunneling data by analyzing the derivatives of SIN and SIS conductances.