For devices on Nano scale classical physics usually cannot explain transmission of electron through the insulating barrier with higher potential energy than kinetic energy of the tunnelling electrons and in this case the Heisenberg’s uncertainty principle takes place.
Barrier penetration can be explained from Heisenberg’s uncertainty principle:
If we were to say a particle cannot enter a barrier, we would actually say this particle is not there, i.e. its position uncertainty is Δx = 0 in the barrier, but, there is no such thing as Δx = 0
As Δx/Δpx ≠ 0 but ≥ ℏ/2 (2.9)
We already know there is no Δ px = 0 either in nature, things are never at rest completely, they have always some kinetic energy …show more content…
He experimented with pieces of iron and discovered that the resistance increases when the current is in the same direction as the magnetic force and decreases when the current is at 90° to the magnetic force [1].
With the growing demands for higher HDD storage density, other forms of MRs with larger variances of resistance due to applied external magnetic fields were needed to be discovered. Two main forms of MRs are: Tunnel Magneto Resistance (TMR) Giant Magneto Resistance (GMR)
In year 1936Mott suggested that Spin-polarized currents can be generated by exploiting the influence of the spin on the transport properties of the electrons in ferromagnetic conductors. The two main points suggested by Mott ,First the electrical conductivity in metal can be explained in term of two largely independent conducting channels, corresponding to spin up and spin down electrons also spin up and spin down electron does not mix over large distance, therefore electrical conduction occur in parallel for two spin channels. Secondly the scattering rate of spin up and spin down electron are quite different whatever the nature of scattering region is. Various magneto-resistive phenomena can be explained by this model when further extended and helped in discovery of the two main forms of Magneto Resistance that are Tunnel Magneto Resistance and Giant Magneto Resistance
Barrier penetration can be explained from Heisenberg’s uncertainty principle:
If we were to say a particle cannot enter a barrier, we would actually say this particle is not there, i.e. its position uncertainty is Δx = 0 in the barrier, but, there is no such thing as Δx = 0
As Δx/Δpx ≠ 0 but ≥ ℏ/2 (2.9)
We already know there is no Δ px = 0 either in nature, things are never at rest completely, they have always some kinetic energy …show more content…
He experimented with pieces of iron and discovered that the resistance increases when the current is in the same direction as the magnetic force and decreases when the current is at 90° to the magnetic force [1].
With the growing demands for higher HDD storage density, other forms of MRs with larger variances of resistance due to applied external magnetic fields were needed to be discovered. Two main forms of MRs are: Tunnel Magneto Resistance (TMR) Giant Magneto Resistance (GMR)
In year 1936Mott suggested that Spin-polarized currents can be generated by exploiting the influence of the spin on the transport properties of the electrons in ferromagnetic conductors. The two main points suggested by Mott ,First the electrical conductivity in metal can be explained in term of two largely independent conducting channels, corresponding to spin up and spin down electrons also spin up and spin down electron does not mix over large distance, therefore electrical conduction occur in parallel for two spin channels. Secondly the scattering rate of spin up and spin down electron are quite different whatever the nature of scattering region is. Various magneto-resistive phenomena can be explained by this model when further extended and helped in discovery of the two main forms of Magneto Resistance that are Tunnel Magneto Resistance and Giant Magneto Resistance