An angle theta1 formed by the end, closer to the pole center, of the portion of a first non-magnetic layer (4) which is in the vicinity of a rotor surface and an interpole, and an angle theta2 formed by the end, closer to the pole center, of the portion of a second non-magnetic layer (5) which is in thevicinity of a rotor surface and an interpole satisfy the following expressions, when polar logarithm is Pn. 0 < theta1 < 180/(5.Pn) and 180/(5.Pn)<= theta2 <= 180 x 2/(5.Pn), or 0 < theta1 < 180 /(7.Pn) and 180/(7.Pn) <= theta2 <= 180 x 2/(7.Pn) Accordingly, the specific degree, fifth-degree orseventh-degree for example, of a magnetic flux density distribution waveform (induction voltage waveform) is reduced while ensuring a sufficient magnetic flux, and unnecessary radial force or thrust force is not produced.