The invention pertains to a head-disk assembly device, “mass spin-valve” or “gravitational rectifier” and method of producing gravitomagnetic induction utilizing Nano-features; Nano-bumps and Nano-pits; fabricated on the surface of a hard disk. The device includes a computer hard disk; a piezoelectric glide head and/or a GMR read head; a typical hard drive's electronics; wherein, defects are fabricated on the said disk using a Focused Ion Beam (FIB) by depositing requisite number of nanobumps of specified height, and etching equal number of nanopits of specified depth a few mils or mm apart on a pre-decided radius. By spinning the said nano-features disk produce (1) an associated mechanical force utilizing a piezoelectric glide head and/or (2) an associated magnetic force utilizing a GMR read head; for (a) general use in surface characterization work and (b) for producing power by the presence or the absence of matter on a spinning disk.