Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Schwinger-Keldysh semionic approach for quantum spin systems.

M N Kiselev1, R Oppermann

  • 1Institut für Theoretische Physik, Universität Würzburg, D-97074 Würzburg, Germany.

Physical Review Letters
|January 3, 2001
PubMed
Summary

We developed a new path-integral Schwinger-Keldysh approach for quantum spin systems using a semionic representation. This method exactly accounts for local constraints, simplifying diagram techniques for models like the Heisenberg model.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Thermoelectric Transport in a Three-Channel Charge Kondo Circuit.

Physical review letters·2020
Same author

Coupled multiple-mode theory for s<sub>±</sub> pairing mechanism in iron based superconductors.

Scientific reports·2016
Same author

Spin-mediated Photomechanical Coupling of a Nanoelectromechanical Shuttle.

Physical review letters·2016
Same author

Kondo force in shuttling devices: dynamical probe for a Kondo cloud.

Physical review letters·2013
Same author

Universality class of replica symmetry breaking, scaling behavior, and the low-temperature fixed-point order function of the Sherrington-Kirkpatrick model.

Physical review. E, Statistical, nonlinear, and soft matter physics·2009
Same author

Spin gap and string order parameter in the ferromagnetic spiral staircase heisenberg ladder: a quantum Monte Carlo study.

Physical review letters·2008

Area of Science:

  • Condensed Matter Physics
  • Quantum Mechanics
  • Many-Body Physics

Background:

  • Quantum spin systems are crucial in condensed matter physics.
  • Existing representations like Holstein-Primakoff and Dyson-Maleev have limitations in handling local constraints.
  • Developing efficient theoretical frameworks is essential for understanding complex magnetic phenomena.

Purpose of the Study:

  • To derive a novel path-integral Schwinger-Keldysh approach for quantum spin systems.
  • To introduce a semionic representation of spins as fermions with imaginary chemical potential.
  • To establish a simplified diagrammatic technique that exactly incorporates local constraints.

Main Methods:

  • Utilizing a semionic representation of spins.
  • Employing an imaginary chemical potential for fermions.

Related Experiment Videos

  • Developing a path-integral formulation within the Schwinger-Keldysh formalism.
  • Applying the standard Feynman diagram technique.
  • Main Results:

    • A new path-integral Schwinger-Keldysh approach for quantum spin systems is derived.
    • The semionic representation allows for exact treatment of local constraints.
    • A standard diagram technique with Feynman rules is established.
    • The approach is demonstrated on the Heisenberg model for Néel and spin-liquid states.

    Conclusions:

    • The derived approach offers a significant simplification compared to other representations.
    • This method provides an exact and efficient tool for studying quantum spin systems.
    • The technique is applicable to various magnetic phases, including Néel and spin-liquid states.