Method and system for providing spin transfer based logic devices
View Patent ↗A method and system for providing a logic device are described. The logic device includes a plurality of magnetic input/channel regions, at least one magnetic sensor region, and at least one sensor coupled with the at least one magnetic sensor region. Each of the magnetic input/channel regions is magnetically biased in a first direction. The magnetic sensor region(s) are magnetically biased in a second direction different from the first direction such that at least one domain wall resides in the magnetic input/channel regions if the logic device is in a quiescent state. The sensor(s) output a signal based on a magnetic state of the magnetic sensor region(s). The input/channel regions and the magnetic sensor region(s) are configured such that the domain wall(s) may move into the magnetic sensor region(s) in response to a logic signal being provided to at least a portion of the magnetic input regions.
1. A logic device comprising:
a plurality of magnetic input/channel regions, each of the plurality of magnetic input/channel regions being magnetically biased in a first direction;
at least one magnetic sensor region being magnetically biased in a second direction different from the first direction such that at least one domain wall resides in the plurality of magnetic input/channel regions if the logic device is in a quiescent state; and
at least one sensor coupled with the at least one magnetic sensor region, the at least one sensor for outputting a signal based on a magnetic state of the at least one magnetic sensor region;
wherein the plurality of input/channel regions and the at least one magnetic sensor region are configured such that the at least one domain wall may move into the at least one magnetic sensor region in response to a logic signal being provided to at least a portion of the plurality of magnetic input regions.
2. The logic device of claim 1 wherein each of the plurality of magnetic input/channel regions has a corresponding input cross-sectional area and the at least one magnetic sensor region has a corresponding sensor cross-sectional area greater than the input cross-sectional area.
3. The logic device of claim 2 wherein the plurality of magnetic input/channel regions consists of three magnetic input channel regions and wherein the sensor cross-sectional area is twice the input cross-sectional area.
4. The logic device of claim 3 wherein one of the three magnetic input channel regions is coupled with a supply voltage.
5. The logic device of claim 2 wherein the each of the plurality of magnetic input/channel regions has a first thickness and wherein the at least one sensor region has a second thickness greater than the first thickness.
6. The logic device of claim 2 wherein the plurality of magnetic input/channel regions consists of two magnetic input channel regions and wherein the sensor cross-sectional area is twice the input cross-sectional area.
7. The logic device of claim 1 wherein the first direction is substantially perpendicular to a plane of the plurality of magnetic input regions and wherein the second direction is antiparallel to the first direction.
8. The logic device of claim 1 further comprising:
a plurality of input electrodes corresponding to the plurality input/channel regions.
9. The logic device of claim 8 further comprising:
a ground electrode, the at least one sensor residing between the plurality of input/channel regions and the ground.
10. The logic device of claim 9 further comprising:
an additional ground electrode, the at least one sensor region residing between the additional ground electrode and the at least one sensor.
11. The logic device of claim 1 the each of the at least one sensor further includes:
a nonmagnetic spacer layer; and
a pinned layer, the nonmagnetic spacer layer residing between the pinned layer and the at least one sensor region.
12. The logic device of claim 11 wherein the nonmagnetic spacer layer is a tunneling barrier layer.
13. The logic device of claim 1 wherein
wherein the plurality of input/channel regions and the at least one magnetic sensor region are configured such that the at least one domain wall may move due to spin transfer torque.
14. A logic device comprising:
a plurality of input electrode;
a plurality of magnetic input/channel regions corresponding to the plurality of input electrodes, each of the plurality of magnetic input/channel regions being magnetically biased in a first direction and having a cross-sectional area, one of the plurality of magnetic input/channels regions being coupled with a bias voltage;
at least one magnetic sensor region having a sensor region cross-sectional area greater than the cross-sectional area, being magnetically biased in a second direction different from the first direction such that at least one domain wall resides in the plurality of magnetic input/channel regions if the logic device is in a quiescent state; and
at least one sensor coupled with the at least one magnetic sensor region, each of the at least one sensor including a free layer and a nonmagnetic spacer layer residing between the at least one magnetic sensor region and the free layer, the at least one magnetic sensor region being a free layer for the at least one sensor;
wherein the plurality of input/channel regions and the at least one magnetic sensor region are configured such that the at least one domain wall may move into the at least one magnetic sensor region in response to spin transfer torque due to a logic signal being provided to at least a portion of the plurality of magnetic input regions.
15. A method for providing a logic device comprising:
providing a plurality of magnetic input/channel regions, each of the plurality of magnetic input/channel regions being magnetically biased in a first direction;
providing at least one magnetic sensor region being magnetically biased in a second direction different from the first direction such that at least one domain wall resides in the plurality of magnetic input/channel regions if the logic device is in a quiescent state; and
providing at least one sensor coupled with the at least one magnetic sensor region, the at least one sensor for outputting a signal based on a magnetic state of the at least one magnetic sensor region;
wherein the plurality of input/channel regions and the at least one magnetic sensor region are configured such that the at least one domain wall may move into the at least one magnetic sensor region in response to a logic signal being provided to at least a portion of the plurality of magnetic input regions.
16. The method of claim 15 wherein each of the plurality of magnetic input/channel regions has a corresponding input cross-sectional area and the at least one magnetic sensor region has a corresponding sensor cross-sectional area greater than the input cross-sectional area.
17. The method of claim 16 wherein the each of the plurality of magnetic input/channel regions has a first thickness and wherein the at least one sensor region has a second thickness greater than the first thickness.
18. The method of claim 15 wherein the first direction is substantially perpendicular to a plane of the plurality of magnetic input regions and wherein the second direction is antiparallel to the first direction.
19. The method of claim 15 further comprising:
providing a plurality of input electrodes corresponding to the plurality input/channel regions.
20. The method of claim 19 further comprising:
providing a ground electrode, the at least one sensor residing between the plurality of input/channel regions and the ground.
21. The method of claim 20 further comprising:
providing an additional ground electrode, the at least one sensor region residing between the additional ground electrode and the at least one sensor.
22. The method of claim 15 wherein the step of providing the at least one sensor further includes:
providing a nonmagnetic spacer layer; and
providing a pinned layer, the nonmagnetic spacer layer residing between the pinned layer and the at least one sensor region.