@article{CTT100752709, author = {Satoshi Hirata and Nobuyuki Kurita and HIDEKAZU TANAKA}, title = {Quasi-two-dimensional Bose-Einstein condensation of lattice bosons in spin-1/2 XXZ ferromagnet K2CuF4}, journal = {Phys. Rev. B}, year = 2017, } @article{CTT100714496, author = {T. Ono and K. Matan and Y. Nambu and T. J. Sato and Kazuya Katayama and Satoshi Hirata and H. Tanaka}, title = {Large Negative Quantum Renormalization of Excitation Energies in the Spin 1/2 Kagome lattice Antiferromagnet}, journal = {J. Phys. Soc. Jpn.}, year = 2014, }