Magnetic tunnel junction and memristor apparatus
A magnetic memory device includes a magnetic tunnel junction having a free magnetic layer having a magnetization orientation that is switchable between a high resistance state magnetization orientation and a low resistance state magnetization orientation and a memristor solid state element electrically coupled to the magnetic tunnel junction. The memristor has a device response that is an integrated voltage versus an integrated current.
1. A magnetic memory device comprising:
a magnetic tunnel junction comprising a free magnetic layer having a magnetization orientation that is switchable between a high resistance state magnetization orientation and a low resistance state magnetization orientation; and
a memristor solid state element electrically coupled to the magnetic tunnel junction, the memristor comprises a varying resistance layer that increases in resistance as a function of an amount of charge passing though the memristor solid state element and the varying resistance layer has a thickness from 1 to 100 nanometers.
2. A magnetic memory device according to claim 1 , wherein the memristor solid state element is in serial electrical connection with the magnetic tunnel junction.
3. A magnetic memory device according to claim 1 , wherein the varying resistance layer has a thickness from 1 to 25 nanometers.
4. A magnetic memory device according to claim 1 , wherein the memristor solid state element measures total current passing through the magnetic tunnel junction.
5. A method of measuring magnetic fluctuations in a magnetic tunnel junction comprising:
passing a current through a magnetic tunnel junction and a memristor solid state element, the memristor solid state element comprises a varying resistance layer that increases in resistance as a function of an amount of current passing though the memristor solid state element to obtain a total memristor current value; and
determining a magnetic fluctuation value by subtracting a total baseline current value from the total memristor current value.
6. A method according to claim 5 , wherein the total baseline current value is determined when the magnetic tunnel junction possesses a constant high resistance saturation state.
7. A method according to claim 5 , wherein the total baseline current value is determined when the magnetic tunnel junction possesses a constant low resistance saturation state.
8. A method according to claim 6 , wherein the total memristor current value is less than the total baseline current value.
9. A method according to claim 7 , wherein the total memristor current value is greater than the total baseline current value.
10. A method according to claim 5 , further comprising reading the total memristor current value with a sense amplifier in electrical connection with the memristor solid state device.
11. A method according to claim 10 , wherein the sense amplifier is in parallel electrical connection with the memristor solid state device.
12. A method according to claim 10 , wherein the sense amplifier is in serial electrical connection with the memristor solid state device.
13. A method according to claim 10 , further comprising resetting the memristor solid state device by passing a current through the memristor solid state device in a direction opposing the passing step current direction.
14. A method according to claim 10 , wherein the memristor solid state element comprises a varying resistance layer, the varying resistance layer comprising a high resistance layer and a low resistance layer comprising oxygen vacancies, the varying resistance layer having a thickness of 10 nanometers or less.
15. A method according to claim 14 , wherein a thickness of the high resistance layer and a thickness of the low resistance layer change as a function of an amount of charge passing thorough the memristor solid state element.
16. A method according to claim 10 , wherein the memristor solid state element measures total current passing through the magnetic tunnel junction.
17. A method of monitoring power consumed by an electrical device comprising:
passing current through a memristor solid state element and an electrical device, the memristor solid state element measuring the current passing through the memristor solid state element and forming a memristance value, the memristor solid state element comprises a varying resistance layer that increases in resistance as a function of an amount of current passing though the memristor solid state element to obtain memristance value; and
reading the memristance value to determine the power consumed by the electrical device;
wherein the memristor solid state element and an electrical device are in parallel electrical connection and the current is provided with a constant current source.
18. The method according to claim 17 , wherein the memristor solid state element and an electrical device are in serial electrical connection and the current is provided with a constant voltage source.