Abstract: In an embodiment of the invention, a trilayer magnetoresistive sensor comprises an underlayer on which a first free layer is deposited. A barrier layer is then deposited after which a second free layer is deposited. A capping layer is then deposited above second free layer. The first free layer is a layer which includes at least a layer of a nitride of an element including at least one of Fe, Co, or Ni, or a multiple laminate structure of a layer containing a nitride of an element including at least one of Fe, Co, Ni and another ferromagnetic layer containing at least one of Fe, Co, or Ni. The combination of the first and second free layers causes anti-parallel coupling.