Bond-bending and bond-stretching phonons in ferromagneticLa0.7Sr0.3MnO3
نویسندگان
چکیده
منابع مشابه
Charge dynamics of t-J model and anomalous bond-stretching phonons in cuprates
The density response of a doped Mott-Hubbard insulator is discussed starting from the t-J model in a slave boson 1/N representation. In leading order O(1) the density fluctuation spectra N(q,ω) are determined by an undamped collective mode at large momentum transfer, in striking disagreement with results obtained by exact diagonalization, which reveal a very broad dispersive peak, reminescent o...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2005
ISSN: 1098-0121,1550-235X
DOI: 10.1103/physrevb.71.092301