US 12,087,339 B2
Magnetic recording medium with multiple soft underlayers and magnetic recording apparatus for use therewith
Asif Bashir, San Jose, CA (US); Pierre-Olivier Jubert, San Jose, CA (US); Antony Ajan, San Jose, CA (US); and Paul Christopher Dorsey, Los Altos, CA (US)
Assigned to Western Digital Technologies, Inc., San Jose, CA (US)
Filed by Western Digital Technologies, Inc., San Jose, CA (US)
Filed on Jul. 25, 2023, as Appl. No. 18/226,026.
Claims priority of provisional application 63/417,622, filed on Oct. 19, 2022.
Prior Publication US 2024/0135969 A1, Apr. 25, 2024
Prior Publication US 2024/0233763 A9, Jul. 11, 2024
Int. Cl. G11B 5/66 (2006.01); G11B 5/00 (2006.01); G11B 5/73 (2006.01); G11B 5/78 (2006.01)
CPC G11B 5/7375 (2019.05) [G11B 5/7369 (2019.05); G11B 2005/0021 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A magnetic recording medium comprising:
a substrate;
a first soft underlayer (SUL) on the substrate, wherein the first SUL is configured and positioned within the magnetic recording medium to provide a first return path for magnetic flux;
a heatsink layer on the first SUL;
a second SUL on the heatsink layer, wherein the second SUL is configured and positioned within the magnetic recording medium to provide a second return path, different from the first return path, for magnetic flux; and
a magnetic recording layer on the second SUL; and
wherein the first SUL and the second SUL each comprises a material with a saturated magnetic flux density greater than 1.2 Tesla.