Thermoelectric voltage-based differential contact sensor

A hard-disk drive, comprising:

• a head slider comprising a thermoelectric embedded contact sensor;
• a magnetic-recording disk rotatably mounted on a spindle;
• and
• a voice coil motor configured to move the head slider to access portions of said magnetic-recording disk,
• wherein the thermoelectric embedded contact sensor comprises a first conductive lead, a second conductive lead, and a metallic component, wherein the metallic component has a different Seebeck coefficient than the first and second conductive leads, and
• wherein the thermoelectric embedded contact sensor is configured to measure the distance between the head slider and the magnetic-recording disk without a supply of a electrical current from the hard-disk drive.