LEED: Surface of Si Si(111) Si(100) · Estimation of the temperature needed (e.g. 23 Na) : 3...
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Wave-particle dualism: Wave-character of particles LEED: Surface of Si Si(100) Si(111)
Transcript of LEED: Surface of Si Si(111) Si(100) · Estimation of the temperature needed (e.g. 23 Na) : 3...
Wave-particle dualism: Wave-character of particles
LEED: Surface of Si
Si(100)Si(111)
Wave-particle dualism: Wave-character of particles
LEED: Electron Energy and LEED Pattern of ZnO[1120]
Ekin=63.9eV
λλλλdeBroglie=1.5ÅEkin=132.1eV
λλλλdeBroglie=1.1Å
Wave-particle dualism: Wave-character of particles
LEED: Reconstruction of the Surface
Si[100] - unreconstructed Si[100] - reconstructed
Wave-particle dualism: Wave-character of particles
LEED: Reconstruction of the Surface Si[111] - H-terminated
Si[111] - 7x7 reconstructed
Wave-particle dualism: Wave-character of particles
LEED: Facets on ZnO@SiC
Estimation of the temperature needed (e.g. 23Na) :
� 3 orthogonal pairs of Lasers in opposite direction
⇒ Pressure by radiation
� Wave length of the Lasers is slightly lower than
the resonance line of the atom ⇒ Doppler effect
⇒ only out-moving atoms can absorb the Laser
light
� Therefore atoms will be decelerated
� Emission of the absorbed light is isotrop ⇒ no
resulting impulse onto the atom
� Superposition of magnetic field ⇒ increases
the capture time
� But: End temperature only 24µK !
���� Atoms : The Bose-Einstein Condensation
Wave-particle dualism: Wave-character of particles
Fourier-Transformation
∫∞
−⋅=0
)()(),( ωωξ ωdeAzt
kzti
Fourier-Transformation:
∫∞
−⋅=0
)(),(1
)( dteztAkzti ωξ
πω
Inverse Fourier-Transf.:
)sin()cos()(
kztikztkzti
e −⋅+−=−
ωωω
Komplexe Exponential-Funktion:
Heisenberg’s Uncertainty Relation
