Raman scattering for triangular lattices spin-12 Heisenberg antiferromagnets
نویسندگان
چکیده
Motivated by various spin-1/2 compounds like Cs2CuCl4 or κ-(BEDTTTF)2Cu2(CN)3, we derive a Raman-scattering operator à la Shastry and Shraiman for various geometries. For T=0, the exact spectra is computed by Lanczos algorithm for finite-size clusters. We perform a systematic investigation as a function of J2/J1, the exchange constant ratio: ranging from J2 = 0, the well known square-lattice case, to J2/J1 = 1 the isotropic triangular lattice. We discuss the polarization dependence of the spectra and show how it can be used to detect precursors of the instabilities of the ground state against quantum fluctuations.
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تاریخ انتشار 2006