Search results
Results from the WOW.Com Content Network
In condensed matter physics, Bloch's theorem states that solutions to the Schrödinger equation in a periodic potential can be expressed as plane waves modulated by periodic functions. The theorem is named after the Swiss physicist Felix Bloch , who discovered the theorem in 1929. [ 1 ]
The ansatz is the special case of electron waves in a periodic crystal lattice using Bloch's theorem as treated generally in the dynamical theory of diffraction. Every crystal is a periodic structure which can be characterized by a Bravais lattice , and for each Bravais lattice we can determine the reciprocal lattice , which encapsulates the ...
Bloch's theorem was inspired by the following theorem of Georges Valiron: Theorem. If f is a non-constant entire function then there exist disks D of arbitrarily large radius and analytic functions φ in D such that f(φ(z)) = z for z in D. Bloch's theorem corresponds to Valiron's theorem via the so-called Bloch's principle.
Real part of the type of solution to the one-dimensional Schrödinger equation that corresponds to the bulk states. These states have Bloch character in the bulk, while decaying exponentially into the vacuum. Figure 3. Real part of the type of solution to the one-dimensional Schrödinger equation that corresponds to surface states.
Using Bloch's theorem, we only need to find a solution for a single period, make sure it is continuous and smooth, and to make sure the function u(x) is also continuous and smooth. Considering a single period of the potential: We have two regions here. We will solve for each independently: Let E be an energy value above the well (E>0)
The solutions in this case are known as Bloch states. Since Bloch's theorem applies only to periodic potentials, and since unceasing random movements of atoms in a crystal disrupt periodicity, this use of Bloch's theorem is only an approximation, but it has proven to be a tremendously valuable approximation, without which most solid-state ...
The Bloch's function is an exact eigensolution for the wave function of an electron in a periodic crystal potential corresponding to an energy (), and is spread over the entire crystal volume. Using the Fourier transform analysis, a spatially localized wave function for the m -th energy band can be constructed from multiple Bloch's functions:
Although, the problem of electrons in a solid is in principle a many-electron problem, in independent electron approximation each electron is subjected to the one-electron Schrödinger equation with a periodic potential and is known as Bloch electron [7] (in contrast to free particles, to which Bloch electrons reduce when the periodic potential ...