کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8201877 1529848 2015 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Leggett's modes in magnetic systems with Jahn-Teller distortion
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک و نجوم (عمومی)
پیش نمایش صفحه اول مقاله
Leggett's modes in magnetic systems with Jahn-Teller distortion
چکیده انگلیسی
Leggett's mode is a collective excitation corresponding to the oscillation of the relative phase of the order parameters in a two band superconductor, with frequency proportional to interband coupling. We report on the existence of modes, similar to Leggett's mode, in magnetic systems with Jahn-Teller distortion. The minimal Kugel-Khomskii model, which describes simultaneously both the spin and the orbital order, is studied. The dynamical degrees of freedom are spin-s operators of localized spins and pseudospin-τ operators, which respond to the orbital degeneracy and satisfy the similar commutation relation with those of the spin operators. In the case of “G-type antiferro” spin and pseudospin order the system possesses two antiferromagnetic magnons with equal spin-wave velocities and two Leggett's modes with equal gaps proportional to the square root of the spin-pseudospin interaction constant. In the case of “ferro” spin and pseudospin order the system possesses one ferromagnetic magnon and one Leggett's mode with gap proportional to the spin-pseudospin interaction constant. We conclude that Leggett's modes, in the spectrum of the magnetic systems with Jahn-Teller distortion, are generic features of these systems.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Annals of Physics - Volume 363, December 2015, Pages 371-384
نویسندگان
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