Quasimomentum of an elementary excitation for a system of point bosons under zero boundary conditions

Authors

  • M.D. Tomchenko Bogolyubov Institute for Theoretical Physics of the NAS of Ukraine, Kyiv

DOI:

https://doi.org/10.15407/dopovidi2019.12.049

Keywords:

elementary excitation, point bosons, quasimomentum, zero boundary conditions

Abstract

As is known, an elementary excitation of a many-particle system with boundaries is not characterized by a definite momentum. We obtain the formula for the quasimomentum of an elementary excitation for a one-dimensional system of N spinless point bosons under zero boundary conditions (BCs). In this case, we use Gaudin's solutions obtained with the help of the Bethe ansatz. We have also found the dispersion laws of the particle-like and hole-like excita tions under zero BCs. They coincide with the known dispersion laws obtained under periodic BCs.

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References

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Published

24.04.2024

How to Cite

Tomchenko, M. (2024). Quasimomentum of an elementary excitation for a system of point bosons under zero boundary conditions . Reports of the National Academy of Sciences of Ukraine, (12), 49–56. https://doi.org/10.15407/dopovidi2019.12.049