Novel Ultra-Sensitive Air Bearing Excitation Based Resonance Contact Detection in Heat Assisted Magnetic Recording (HAMR)

Resonance based enhanced contact detection is investigated at high sliding head-disk interface of hard disk drives. Acoustic signal arising from the contact in between the head and the disk is dominated by the resonance of the head air bearing frequencies. We show that modulation the head at resonance during the contact enhances greatly the acoustic signal generated during the contact between the head and the disk. As an application for HAMR HDDs, we used this scheme to detect the contact in between the near field transducer (NFT) and the disk which so far has been elusive.