A read/write head includes a slider provided with an electromagnetic transducer element (or an optical module), an actuator, and a suspension. The actuator includes a fixed part, a movable part, and at least two beam members for coupling them together. The beam members have a displacement generating means that elongates and contracts by inverse piezoelectric effect or electrostrictive effect. The fixed part is fixed to the suspension, and the movable part is fixed to the slider. Upon the elongation and contraction of the displacement generator, the displacement generator deflects and the movable part displaces linearly, circularly or rotationally with respect to the fixed part, and the electromagnetic transducer element displaces in a linear or circular orbit, so that the electromagnetic transducer element intersects recording tracks. In the actuator, the fixed part, movable part and beam members are formed as an integrated single piece by providing a hole and/or a cutout in a sheet-like member constructed of a piezoelectric or electrostrictive material. The actuator of the structure illustrated is used for the positioning of a direction intersecting recording tracks. In this case, the total sum of voltages applied on the displacement generating means is controlled in such a manner that it is constant at any time, thereby controlling position fluctuations of the electromagnetic transducer element in the direction vertical to the recording medium surface.