Two-dimensional magnetic recording

Two-dimensional magnetic recording (TDMR) is a technology introduced in 2017 in hard disk drives (HDD) used for computer data storage.

TDMR allows greater storage capacity by advantageously combining signals simultaneously from multiple read-back heads to enhance the recovery of one or more data-tracks.

[5][6] In the initial concept, the data-tracks were assumed to be very narrow tracks created by shingled recording and subject to considerable mutual interference.

[9][10][11][12][13] However, the technical challenge of creating an array of closely spaced read-heads and the complexity of jointly detecting data simultaneously on several tracks are both considerable.

Current implementations recover only a single track using a read head with just two read-elements stacked one above the other (i.e. downtrack) and rely on the skew arising from the use of a rotary actuator to create some cross-track separation between the sensors.