Chopstick
09-26-2007, 04:03 PM
FERROMAGNETIC DOUBLE QUANTUM WELL TUNNEL MAGNETO-RESISTANCE DEVICE
A ferromagnetic double quantum well tunnel magneto-resistance device which can obtain an infinite tunnel magneto-resistance ratio with a required bias voltage by utilizing a 2-dimensional electron (positive hole) system, a high sensitivity sensor utilizing the device and a nonvolatile memory device utilizing the device. A ferromagnetic 1st quantum well layer (4) and a ferromagnetic 2nd quantum well layer (8) in which carrier quanta are confined in 2-dimensional electron (positive hole) states are held between nonmagnetic barrier layers (2, 6 and 10) through which tunneling is enabled. By providing a difference in coercive force between the 1st quantum well layer (4) and the 2nd quantum well layer (8), magnetization of only one of the quantum wells is reversed by external magnetic field. When the magnetization directions of the two quantum wells are in parallel with each other, the tunneling is enabled and, when the magnetization directions of the two quantum wells are in reverse-parallel with each other, the tunneling is prohibited, so that the infinite tunnel magneto-resistance ratio can be obtained.
<font color="blue"> I WANT ONE!</font color> /ccboard/images/graemlins/laugh.gif
A ferromagnetic double quantum well tunnel magneto-resistance device which can obtain an infinite tunnel magneto-resistance ratio with a required bias voltage by utilizing a 2-dimensional electron (positive hole) system, a high sensitivity sensor utilizing the device and a nonvolatile memory device utilizing the device. A ferromagnetic 1st quantum well layer (4) and a ferromagnetic 2nd quantum well layer (8) in which carrier quanta are confined in 2-dimensional electron (positive hole) states are held between nonmagnetic barrier layers (2, 6 and 10) through which tunneling is enabled. By providing a difference in coercive force between the 1st quantum well layer (4) and the 2nd quantum well layer (8), magnetization of only one of the quantum wells is reversed by external magnetic field. When the magnetization directions of the two quantum wells are in parallel with each other, the tunneling is enabled and, when the magnetization directions of the two quantum wells are in reverse-parallel with each other, the tunneling is prohibited, so that the infinite tunnel magneto-resistance ratio can be obtained.
<font color="blue"> I WANT ONE!</font color> /ccboard/images/graemlins/laugh.gif