What is perpendicular recording on hard drives?

I already commented on this subject in another tutorial but as the subject is very interesting for the curious, I decided to focus this item on a new post.

A modern hard drive uses the type of perpendicular recording, but what exactly is this?

Long ago, hard drives used the longitudinal method, where the sectors on the disk are laid out in their lying state allowing for easy conversion of their polarization.

This method was developed because the only way to successfully magnetize an iron ferrite was to magnetize the north and south pole at the same time.

See the following example of what it was like before and the new format:

In the first case, the arm reached both sides, but the space was compromised because all sectors needed to lie down.

In the second example, they studied and were successful with a method of sending the negative pole over several sectors at the same time, reaching the bottom of the disk sectors.

The sign of the negative pole is much weaker but broad, to the point of not damaging other sectors when passing over them, reaching the layer below.

The modified sectors are those that contain the complete magnetic connection, that is, receiving only one of the signals, according to the studies carried out, does not change the magnetic state and, for this reason, they were able to reduce the sector allocation space and increase the amount of data per recorded area .

New studies want to reduce the area of ​​distance between sectors even more, even if the arm is not as small as the sector, that is, the magnetization could occur in some intensity in nearby sectors, but with the help of error correction mechanisms, the disk could scan and recover lost data transparently to the user.

It is well known that perpendicular recording is considered to be a case of speculation that discs are more sensitive to data loss and excessive deterioration in all sectors, but companies have sought to create increasingly efficient security mechanisms and error correction controls. to ensure data integrity and maximum data storage in smaller areas.