Anomalous spin waves and the commensurate-incommensurate magnetic phase transition in LiNiPO4
| Title | Anomalous spin waves and the commensurate-incommensurate magnetic phase transition in LiNiPO4 |
| Publication Type | Journal Article |
| Year of Publication | 2009 |
| Authors | Jensen TBS, Christensen NB, Kenzelmann M, Ronnow HM, Niedermayer C, Andersen NH, Lefmann K, Jimenez-Ruiz M, Demmel F, Li J, Zarestky JL, Vaknin D |
| Journal Title | Physical Review B |
| Volume | 79 |
| Pages | 092413 |
| Date Published | 03/01 |
| ISBN Number | 1098-0121 |
| Accession Number | ISI:000264768200016 |
| Keywords | antiferromagnetic materials, commensurate-incommensurate transformations, exchange interactions (electron), heisenberg model, lithium compounds, magnetic anisotropy, magnetic transitions, magnetoelectric effects, neutron diffraction, nickel compounds, spi |
| Abstract | Detailed spin-wave spectra of magnetoelectric LiNiPO4 have been measured by neutron scattering at low temperatures in the commensurate (C) antiferromagnetic (AF) phase below T-N=20.8 K. An anomalous shallow minimum is observed at the modulation vector of the incommensurate (IC) AF phase appearing above T-N. A linear spin-wave model based on Heisenberg exchange couplings and single-ion anisotropies accounts for all the observed spin-wave dispersions and intensities. Along the b axis an unusually strong next-nearest-neighbor AF coupling competes with the dominant nearest-neighbor AF exchange interaction and causes the IC structure. |
| URL | <Go to ISI>://000264768200016 |
| DOI | 10.1103/Physrevb.79.092413 |
