Multiple-Spin Exchange in Strongly Correlated Fermion Systems

Magnetic Interactions in Molecules and Highly Correlated Materials: Physical Content, Analytical Derivation, and Rigorous Extraction of Magnetic Hamiltonians

“…The J ring terms originate in the cyclic movement of the electrons around the Cu 4 O 4 plaquettes. It has been proposed that the resulting current plays an important role in the mechanism of superconductivity. , Similar four-body terms are crucial to describe the ground-state properties of 3 He, and they are also present in π conjugated systems …”

“…It has been proposed that the resulting current plays an important role in the mechanism of superconductivity. 765,769 Similar fourbody terms are crucial to describe the ground-state properties of 3 He, 770 and they are also present in π conjugated systems. 215 Over the years, several strategies have been developed to evaluate these extra parameters.…”

Discovering correlated fermions using quantum Monte Carlo

“…The sum is over all possible ring exchanges. [24] The computation of the magnetic properties is now reduced to two problems. First, how to determine the J p 's and second, how to solve the resulting Hamiltonian.…”

Thermodynamic properties of an S=12 ring-exchange model on the triangular lattice

“…These exchange interactions can be considered as an introduction of the charge fluctuation [16,17] and thus become more relevant for describing magnetic properties of Mott insulators in proximity of the metal-insulator transition [18][19][20][21][22][23][24][25][26][27]. While the ring-exchange interaction itself has long been considered for describing the magnetism in the three-dimensional solid 3 He [28][29][30][31][32][33][34], NiS 2 [35], and the parent compounds of high-T c cuprate superconductor such as La 2 CuO 4 [36][37][38][39][40][41], its importance in triangular-lattice systems near Mott transition is attracting a renewed attention recently [14,15,42,43] in organic Mott insulators κ-(ET) 2 Cu 2 (CN) 3 [44][45][46] and EtMe 3 Sb[Pd(dmit) 2 ] 2 [47,48], and a charge-density-wave Mott insulator 1T -TaS 2 [49,50].…”