enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Density of states - Wikipedia

    en.wikipedia.org/wiki/Density_of_states

    The density of states related to volume V and N countable energy levels is defined as: = = (()). Because the smallest allowed change of momentum for a particle in a box of dimension and length is () = (/), the volume-related density of states for continuous energy levels is obtained in the limit as ():= (()), Here, is the spatial dimension of the considered system and the wave vector.

  3. Quantum dot - Wikipedia

    en.wikipedia.org/wiki/Quantum_dot

    The energy levels of a single particle in a quantum dot can be predicted using the particle in a box model in which the energies of states depend on the length of the box. For an exciton inside a quantum dot, there is also the Coulomb interaction between the negatively charged electron and the positively charged hole.

  4. Van Hove singularity - Wikipedia

    en.wikipedia.org/wiki/Van_Hove_singularity

    The density of states which appears in the Fermi's Golden Rule expression is then the joint density of states, which is the number of electronic states in the conduction and valence bands that are separated by a given photon energy.

  5. Scanning tunneling spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Scanning_tunneling...

    Mechanism of how density of states influence V-A spectra of tunnel junction. Scanning tunneling spectroscopy is an experimental technique which uses a scanning tunneling microscope (STM) to probe the local density of electronic states (LDOS) and the band gap of surfaces and materials on surfaces at the atomic scale. [1]

  6. Quantum well - Wikipedia

    en.wikipedia.org/wiki/Quantum_well

    Furthermore, the model shows that the energy levels are proportional to the inverse of the effective mass. Consequently, heavy holes and light holes will have different energy states when trapped in the well. Heavy and light holes arise when the maxima of valence bands with different curvature coincide; resulting in two different effective ...

  7. Density matrix - Wikipedia

    en.wikipedia.org/wiki/Density_matrix

    In quantum mechanics, a density matrix (or density operator) is a matrix that describes an ensemble [1] of physical systems as quantum states (even if the ensemble contains only one system). It allows for the calculation of the probabilities of the outcomes of any measurements performed upon the systems of the ensemble using the Born rule .

  8. Degenerate energy levels - Wikipedia

    en.wikipedia.org/wiki/Degenerate_energy_levels

    Degenerate states are also obtained when the sum of squares of quantum numbers corresponding to different energy levels are the same. For example, the three states (n x = 7, n y = 1), (n x = 1, n y = 7) and (n x = n y = 5) all have = and constitute a degenerate set.

  9. Purity (quantum mechanics) - Wikipedia

    en.wikipedia.org/wiki/Purity_(quantum_mechanics)

    It is defined as the integral (or sum for finite system size) over the square of the density in some space, e.g., real space, momentum space, or even phase space, where the densities would be the square of the real space wave function | |, the square of the momentum space wave function | ~ |, or some phase space density like the Husimi ...