3.17 Sspd_chapter1_part 8_conclusion_electron travelling across a

SSPD_Chapter 1_Part 8_conclusion_ ELECTRON TRAVELING ACROSS A STEP POTENTIAL WITH TOTAL ENERGY GREATER THAN THE POTENTIAL BARRIER OFFERED BY THE STEP POTENTIAL.

Fig.(1.32) Electron traveling across a step potential with energy greater than that needed for crossing the barrier potential.

In Figure (1.32) electron is traveling across a step potential with sufficient energy to cross the barrier. The electron matter wave experiences a partial reflection at the step potential just as light experiences a reflection when passing across step change in refractive index.

The linear momentum also changes while moving from one region of potential energy to another region of potential energy,

Thus p 1 ^2 /(2m e ) = (E ) and wave vector k 1 = p 1 /ћ;

And p 2 ^2 /(2m e ) = (E- qV 1 ) and wave vector k 2 = p 2 /ћ; 1.74

The incident wave: ψ I = AExp[i(ωt + |k 1 |z )]

The reflected wave: ψ R = BExp[i(ωt - |k 1 |z )]

The transmitted wave: ψ T = CExp[i(ωt - |k 2 |z )] 1.75

In 1961 , Texas Instrument brought the first IC Chip where the feature size was several microns and which could be analyzed in the classical manner. In microchips the classical properties of the electrons were manifested.

By the turn of century PENTIUM IV INTEL Chip [Appendix XXXVII] has come in the market where the feature size has come below 100nm. These nanochips manifest the quantum mechanical properties of the electrons and are more appropriately called Quantum Chips.

By the use of VLSI/ULSI technology many quantum devices are coming in the market.