Page 91 - Principles and Applications of NanoMEMS Physics
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Chapter  3


             NANOMEMS PHYSICS: QUANTUM WAVE
             PHENOMENA












             3.1  Manifestation of Wave Nature of Electrons


               The principles of nanoscale devices are based on the physics dominating
             this dimensional regime. In particular, as the device size is reduced below
             about 100nm, the electron behavior stops obeying classical physics, in which
             its momentum and  energy are continuous,  and  starts  obeying  quantum
             mechanics, in which it behaves as waves with quantized energy, Figure 3-1.
                   Fig.3-1   Continuous Energy
                                      p  2
                            p =  mv  E ~
                                      2 m


                            L z
                                       L y
                                L x


                                      Size ReductionÆ Quantized Energy
                                        p  =  h  E  =  h ω
                                           λ             2
                                                       y
                                                     ¨
                                                  x
                                                            z
                                      E ( ,nn  ,n  )=  h  ª «¨ §n π · ¸ 2  + §n π · ¸  + §n π · ¸ ¸ 2 º »
                                                           ¨
                                                ¨
                                                           ¨
                                          y
                                        x
                                            z
                                              2m « © L  ¸ ¹  ¨ L  ¸  © L  ¹  »
                                                ¬  x  ©  y  ¹  z  ¼
                                 ~
                                 <
                               L i 100 nm      ∆x  ⋅  ∆p x  > ~  h
                            Figure 3-1. Size-dependent behavior of electrons.
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