Schulenburg J, Honecker A, Schnack J, Richter J, Schmidt H-J
Institut für Theoretische Physik, Universität Magdeburg, P.O. Box 4120, D-39016 Magdeburg, Germany.
Phys Rev Lett. 2002 Apr 22;88(16):167207. doi: 10.1103/PhysRevLett.88.167207. Epub 2002 Apr 8.
For a class of frustrated spin lattices including the Kagomé lattice we construct exact eigenstates consisting of several independent, localized one-magnon states and argue that they are ground states for high magnetic fields. If the maximal number of local magnons scales with the number of spins in the system, which is the case for the Kagomé lattice, the effect persists in the thermodynamic limit and gives rise to a macroscopic jump in the zero-temperature magnetization curve just below the saturation field. The effect decreases with increasing spin quantum number and vanishes in the classical limit. Thus it is a true macroscopic quantum effect.
对于包括 Kagomé 晶格在内的一类受挫自旋晶格，我们构建了由几个独立的、局域化的单磁振子态组成的精确本征态，并论证它们是高磁场下的基态。如果局域磁振子的最大数量与系统中的自旋数成比例，Kagomé 晶格就是这种情况，那么在热力学极限下该效应仍然存在，并在刚好低于饱和场的零温磁化曲线上产生宏观跳跃。该效应随着自旋量子数的增加而减小，并在经典极限下消失。因此，这是一种真正的宏观量子效应。
