berry phase

  1. J

    A Berry phase and parallel transport

    Hello. In the following(p.2): https://michaelberryphysics.files.wordpress.com/2013/07/berry187.pdf Berry uses parallel transport on a sphere to showcase the (an)holonomy angle of a vector when it is parallel transported over a closed loop on the sphere. A clearer illustration of this can be...
  2. J

    A Is the Berry connection compatible with the metric?

    Hello, Is the Berry connection compatible with the metric(covariant derivative of metric vanishes) in the same way that the Levi-Civita connection is compatible with the metric(as in Riemannanian Geometry and General Relativity)? Also, does it have torsion? It must either have torsion or not be...
  3. J

    A Is the Berry connection a Levi-Civita connection?

    Hello! I have learned Riemannian Geometry, so the only connection I have ever worked with is the Levi-Civita connection(covariant derivative of metric tensor vanishes and the Chrystoffel symbols are symmetric). When performing a parallel transport with the L-C connection, angles and lengths are...
  4. L

    I Berry phase, Bra-Ket and gradient

    Could somebody show me how to derive this equation? How can I get right side from left. Step by step, thanks....
  5. L

    A Integration along a loop in the base space of U(1) bundles

    Let ##P## be a ##U(1)## principal bundle over base space ##M##. In physics there are phenomenons related to a loop integration in ##M##, such as the Berry's phase ##\gamma = \oint_C A ## where ##C(t)## is a loop in ##M##, and ##A## is the gauge potential (pull back of connection one-form of...
  6. H

    A Why electrical polarization can be expressed as Berry phase?

    Could we calculate (linear) electric polarizability from Berry phase?
  7. V

    A Question about Berry phase in 1D polyacetylene

    Hi. I'm taking a look at some lectures by Charles Kane, and he uses this simple model of polyacetylene (1D chain of atoms with alternating bonds which give alternating hopping amplitudes) [view attached image]. There are two types of polyacetylene topologically inequivalent. They both give the...
  8. C

    Adiabatic expansion of infinite square well

    1. Homework Statement Suppose that an infinite square well has width L , 0<x<L. Nowthe right wall expands slowly to 2L. Calculate the geometric phase and the dynamic phase for the wave function at the end of this adiabatic expansion of the well. Note: the expansion of the well does not occur...
  9. T

    Matrix elements of non-normalizable states

    Although strictly quantum mechanics is defined in ##L_2## (square integrable function space), non normalizable states exists in literature. In this case, textbooks adopt an alternative normalization condition. for example, for ##\psi_p(x)=\frac{1}{2\pi\hbar}e^{ipx/\hbar}## ##...
  10. J

    Sources to learn about Berry phases and Adiabatic Theorem

    Hello, I recently went through Griffiths' Quantum Mechanics text and there is a chapter called the Adiabatic Theorem that includes Berry phase and the Aharonov-Bohm effect. As I found them very interesting, I would appreciate if anyone could provide me with some good sources(books, internet...
  11. M

    Why there is mod 2pi in Berry phase?

    Some books say that there is a gauge transform that we can put an extra phase e^{i \phi ( R(t))} to the wave function. Since R(t=0) = R(t=T), difference in \phi = 2 pi n, where n is any integers. As gauge transform would lead to 2 pi n difference, berry phase is determined up to 2pi n. However...
Top