Dual FGL and dual SPL spintronic device to reduce perpendicular field at writing location
The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head. The magnetic recording head comprises a main pole, a shield, and a spintronic device disposed between the main pole and the shield. The spintronic device comprises two field generation layers (FGLs), two spin polarization layers (SPLs), and two spin kill layers. The spintronic device further comprises one or more optional thin negative beta material layers, such as layers comprising FeCr, disposed in contact with at least one of the spin kill layers. When electric current is applied, the spin kill layers and optional negative beta material layers eliminate or reduce any spin torque between the FGLs and the SPLs.
1 . A magnetic recording head comprising:
a shield;
a main pole; and
a spintronic device disposed between the shield and the main pole, the spintronic device comprising:
a first spin kill layer disposed over the main pole;
a first negative beta material layer disposed between the main pole and the first spin kill layer;
a first spin polarization layer disposed over the first spin kill layer;
a first field generation layer disposed over the first spin polarization layer;
a second spin kill layer;
a second spin polarization layer; and
a second field generation layer disposed between the first field generation layer and the shield.
2 . The magnetic recording head of claim 1 , wherein the spintronic device further comprises a second negative beta material layer disposed between the first spin kill layer and the first spin polarization layer.
3 . The magnetic recording head of claim 2 , wherein the spintronic device further comprises a third negative beta material layer disposed between the second field generation layer and the second spin kill layer.
4 . The magnetic recording head of claim 3 , wherein the first, second, and third negative beta material layers each individually comprises FeCr, and wherein the first and second spin kill layers each individually comprises a non-magnetic material having a resistivity greater than about 100 nano-Ohm·m.
5 . The magnetic recording head of claim 1 , wherein the spintronic device further comprises:
a first spacer layer disposed between the first field generation layer and the first spin kill layer;
a second spacer layer disposed between the first field generation layer and the second spin polarization layer; and
a third spacer layer disposed between the second field generation layer and the shield.
6 . A magnetic recording device comprising the magnetic recording head of claim 1 , the magnetic recording device configured to flow a current from the main pole through the spintronic device to the shield.
7 . A magnetic recording head comprising:
a shield;
a main pole; and
a spintronic device disposed between the shield and the main pole, the spintronic device comprising:
a first spin kill layer disposed adjacent to the main pole;
a first spin polarization layer;
a first field generation layer;
a second spin kill layer;
a second spin polarization layer;
a second field generation layer disposed adjacent to the shield, wherein the second spin polarization layer is disposed between the first field generation layer and the second field generation layer; and
one or more negative beta material layers disposed between the main pole and the second spin polarization layer.
8 . The magnetic recording head of claim 7 , wherein at least one additional negative beta material layer is disposed in contact with either the first spin kill layer or the second spin kill layer.
9 . The magnetic recording head of claim 7 , wherein the first and second spin kill layers each individually comprises a non-magnetic material having a resistivity greater than about 100 nano-Ohm·m.
10 . The magnetic recording head of claim 7 , wherein each of the one or more negative beta material layers comprises FeCr and has a thickness of about 1 nm.
11 . The magnetic recording head of claim 7 , wherein a first negative beta material layer of the one or more negative beta material layers is disposed in contact with the first spin polarization layer.
12 . The magnetic recording head of claim 11 , wherein a second negative beta material is disposed in contact with the second spin polarization layer.
13 . A magnetic recording device comprising the magnetic recording head of claim 8 , the magnetic recording device configured to flow a current from the main pole through the spintronic device to the shield.
14 . A magnetic recording device, comprising:
a magnetic recording head, the magnetic recording head comprising:
a shield;
a main pole; and
a spintronic device disposed between the shield and the main pole, the spintronic device comprising:
a first spin kill layer disposed adjacent to the main pole;
a first spin polarization layer;
a first field generation layer;
a second spin kill layer, wherein the first and second spin kill layers each individually comprises a non-magnetic material having a resistivity greater than about 100 nano-Ohm·m;
a second spin polarization layer;
a second field generation layer disposed adjacent to the shield, wherein the second spin polarization layer is disposed between the first field generation layer and the second field generation layer; and
one or more negative beta material layers disposed between the main pole and the second spin polarization layer, wherein each of the one or more negative beta material layers comprises FeCr; and
means for flowing a current from the main pole through the spintronic device to the shield.
15 . The magnetic recording device of claim 14 , wherein the first spin kill layer is disposed in contact with the first spin polarization layer.
16 . The magnetic recording device of claim 14 , wherein the second spin kill layer is disposed in contact with the second field generation layer.
17 . The magnetic recording device of claim 14 , wherein a first negative beta material layer of the one or more negative beta material layers is disposed in contact with the first spin polarization layer.
18 . The magnetic recording device of claim 17 , wherein a second negative beta material layer is disposed in contact with the second field generation layer.
19 . The magnetic recording device of claim 14 , wherein at least one additional negative beta material layer is disposed in contact with either the first spin kill layer or the second spin kill layer.