Recent content by fk08

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    Upward Band Bending in n-Type Si Contacted by Metal

    I am a little bit confused about the upward band bending in a n-type Si which is in contact with a metal. Suppose that electrons flow from Si to the metal to align the chemical potentials such that positive donor levels become depleted. In equilibrium one ends up with a negative charge density...
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    Topological Insulator: 100% Spin Polarization & Transport Properties

    Why is it so important to claim that the topologically protected surface states are 100% spin polarized. Is there any connection between the degree of polarization and for instance transport properties, like the absent backscattering of these states at impurities?
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    Back gating of Metal/Semiconductor junction

    When a metal is brought into contact with a semiconductor (n-type) a depletion layer is formed at the metal-semiconductor interface on which band bending occurs. In the full-depletion model it is assumed that all donors are positively charged (withi this layer). What happens if a back-gate (with...
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    Band Bending & Donor Concentration in Semiconductors

    When a n-type semiconductor is brought into contact with a metal, then alignment of the chemical potentials of both systems leads to band bending within the depletion layer, e.g on the semiconductor side. does the amount of band bending (change of potential) also depend on the donor...
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    How can I calculate the number of dopants (atoms/cm^3) from a

    How can I calculate the number of dopants (atoms/cm^3) from a resistance, e.g. R = 50 ohm*cm? Cheers!
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    Valence Band Shift of n-Type Semiconductor

    What does it mean if the valence band of a n-type semiconductor shifts towards lower binding energy after deposition of a metal on-top. Is it simply charge transfer from the metal towards the semiconductor or vice versa? I mean , the valence band is fully occupied, so there are no states for the...
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    Matrix elements in photoemission

    Thanks a lot. But, I couldn't find any paper from this guy about matrix elements... Only things about topological insulators...Can you provide a doi...?
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    Matrix elements in photoemission

    What are the main contributions to the matrix elements (intensity asymmetries with respect to normal emission) in ARPES? Is there a theoretical paper on that?
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    Electron Effective Mass and Effective Mass Theory in Semiconductors

    in simple metals, the effective mass can be related to the orbital overlap. strongly overlapping orbitals give states with free electron like character, whereas a reduced overlap increases the effective mass..
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    What is the difference between Spintronics and GMR Effect?

    The aim of spintronics is to control an injected spin current with an external electric field rather than a magnetic. imagine an spin pointing in positive z-direction that is injected into a Rashba-system, which feautures strong spin-orbit interaction, e.g. the spin orientation depends on the...
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    Velocity of qm particle in a box

    Can I draw conclusions from the curvature of a wavefunction on the kin. energy of the particle? For instance, the lowest bound solution of a particle in the box is a half of sinus: Psi(x) = sin(pi*x/L) Since the second deriv. of a wavefunction is proportional to the kin. energy, this would...
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    ARPES & Hole Lifetime: Exploring the Connection

    Why it is said that ARPES measures the lifetime of the injected photo hole? When photons with certain energy promote electrons from the initial state to the final state with kinetic energy then by knowing the photon energy one can simply determine the binding energy of the initial state: Eb =...
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    Can we easily extract effective masses from Si band structure?

    dear ravian, yes, you can extract the effective mass from your bandstructure. I you have a bandstructure E(k) you can extract energy distribution curves (take the program IGOR for instance) for the momentum range of interest, e.g. E(k1),E(k2) and so on. These photoemission peaks you can...
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    Determining Overlap of Two Gaussians Mathematically

    Hello, how is the overlap of two gaussians determined mathematically? Thanks
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    Calculate Overlap of PZ Orbitals Dependent on Interatomic Distance

    Hello, i would like to calculate the overlap of two simple pz orbitals dependent on the interatomic distance. how can i do that? Thanks
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