Ginzburg-Landau model of Bose-Einstein condensation of magnons
- Department of Physical Electronics, School of Electrical Engineering, Tel Aviv University, Tel Aviv 69978 (Israel)
- Institute for Applied Physics, University of Muenster, 48149 Muenster (Germany)
We introduce a system of phenomenological equations for Bose-Einstein condensates of magnons in the one-dimensional setting. The nonlinearly coupled equations, written for amplitudes of the right- and left-traveling waves, combine basic features of the Gross-Pitaevskii and complex Ginzburg-Landau models. They include localized source terms to represent the microwave magnon-pumping field. With the source represented by the delta functions, we find analytical solutions for symmetric localized states of the magnon condensates. We also predict the existence of asymmetric states with unequal amplitudes of the two components. Numerical simulations demonstrate that all analytically found solutions are stable. With the delta-function terms replaced by broader sources, the simulations reveal a transition from the single-peak stationary symmetric states to multipeak ones, generated by the modulational instability of extended nonlinear-wave patterns. In the simulations, symmetric initial conditions always converge to symmetric stationary patterns. On the other hand, asymmetric inputs may generate nonstationary asymmetric localized solutions, in the form of traveling or standing waves. Comparison with experimental results demonstrates that the phenomenological equations provide for a reasonably good model for the description of the spatiotemporal dynamics of magnon condensates.
- OSTI ID:
- 21366659
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 81, Issue 2; Other Information: DOI: 10.1103/PhysRevB.81.024418; (c) 2010 The American Physical Society; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
Similar Records
Generation of optical and matter-wave solitons in binary systems with a periodically modulated coupling
Radiation of linear waves in the stationary flow of a Bose-Einstein condensate past an obstacle
Related Subjects
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMPLITUDES
ANALYTICAL SOLUTION
ASYMMETRY
BOSE-EINSTEIN CONDENSATION
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
CONDENSATES
DELTA FUNCTION
EQUATIONS
GINZBURG-LANDAU THEORY
INSTABILITY
MAGNONS
MICROWAVE RADIATION
NONLINEAR PROBLEMS
ONE-DIMENSIONAL CALCULATIONS
SOURCE TERMS
STANDING WAVES
SYMMETRY
TRAVELLING WAVES
ELECTROMAGNETIC RADIATION
EVALUATION
FUNCTIONS
MATHEMATICAL SOLUTIONS
QUASI PARTICLES
RADIATIONS
SIMULATION