@article{ISI:000338702600028,
 abstract = {We study Heisenberg spin-1/2 and spin-1 chains with alternating
ferromagnetic (J(1)(F)) and antiferromagnetic (J(1)(A)) nearest-neighbor
interactions and a ferromagnetic next-nearest-neighbor interaction
(J(2)(F)). In this model frustration is present due to the non-zero
J(2)(F). The model with site spin s behaves like a Haldane spin chain,
with site spin 2s in the limit of vanishing J(2)(F) and large
J(1)(F)/J(1)(A). We show that the exact ground state of the model can be
found along a line in the parameter space. For fixed J(1)(F), the phase
diagram in the space of J(1)(A)-J(2)(F) is determined using numerical
techniques complemented by analytical calculations. A number of
quantities, including the structure factor, energy gap, entanglement
entropy and zero temperature magnetization, are studied to understand
the complete phase diagram. An interesting and potentially important
feature of this model is that it can exhibit a macroscopic magnetization
jump in the presence of a magnetic field; we study this using an
effective Hamiltonian.},
 article-number = {276002},
 author = {Sahoo, Shaon and Goli, V. M. L. Durga Prasad and Sen, Diptiman and
Ramasesha, S.},
 doi = {10.1088/0953-8984/26/27/276002},
 eissn = {1361-648X},
 issn = {0953-8984},
 journal = {JOURNAL OF PHYSICS-CONDENSED MATTER},
 month = {JUL 9},
 number = {27},
 orcid-numbers = {Sahoo, Shaon/0000-0003-0299-3408},
 researcherid-numbers = {G, V M L Durga Prasad/C-8943-2018
},
 times-cited = {4},
 title = {Studies on a frustrated Heisenberg spin chain with alternating
ferromagnetic and antiferromagnetic exchanges},
 unique-id = {ISI:000338702600028},
 volume = {26},
 year = {2014}
}