### Low-dimensional spin systems

We are interested in static and dynamical properties of low-dimensional magnetic systems. The work of our group is focused on:

- Magnetization processes in low-dimensional spin systems
- Slow relaxation of magnetization in quasi-1D spin chain systems
- Hysteresis in single chain magnets
- Application of group theoretical methods to spin systems
- Cluster perturbation theory for low-dimensional spin systems
- BEC in dimerized spin systems
- Frustration effects in low-dimensional ferrimagnetic systems

### Chiral helimagnets

A potential application of chiral helimagnets in spintronics devices is of great interest. Our research in the field of chiral helimagnets focuses on:

- Dissipationless spin currents
- Spin torque transfer
- Spin resonance
- Magnetoresistance
- Spin motive force

### Group members:

**A. S. Ovchinnikov**, Associate Professor, Ural Federal University, Alexander.Ovchinnikov@usu.ru**I. G. Bostrem**, Associate Professor, Ural Federal University, Irene.Bostrem@usu.ru**V. E. Sinitsyn**, Associate Professor, Ural Federal University, Valentine.Sinitsyn@usu.ru**I.V. Proskurin**, Assistant, Ural Federal University, iprosk@yandex.ru**Vl. E. Sinitsyn**, postgraduate, Ural Federal University, sinitsyn_ve@mail.ru

### In collaboration with:

**N.V. Baranov**, Professor, Institute of Metal Physics and Ural Fedral University**J. Kishine**, Professor, Open Univeristy of Japan**K. Inoue**, Professor, Hiroshima University

### Publications:

2012

- A.S. Ovchinnikov, V. E. Sinitsyn, I.G. Bostrem, Y. Hosokoshi and K. Inoue, Magnetization and spin gap in two-dimensional organic ferrimagnet BIPNNBNO, Journal of Physics: Condensed Matter 24 (2012).
- Y. Togawa and T. Koyama and K. Takayanagi and S. Mori and Y. Kousaka and J. Akimitsu and S. Nishihara and K. Inoue and A. S. Ovchinnikov and J. Kishine, Phys. Rev. Lett. 108, 107202 (2012)

2011

- J. Kishine and A. S. Ovchinnikov, Canonical formulation of magnetic domain-wall motion, Phys. Lett. A 375, 1824 (2011)
- J. Kishine and A. S. Ovchinnikov and I.V. Proskurin, Tuning Magnetotransport through a Magnetic Kink Crystal in a Chiral Helimagnet, Phys. Rev. Lett. 107, 017205 (2011)
- J. Kishine and A. S. Ovchinnikov and I. V. Proskurin, Nonequilibrium density operator approach to domain wall resistivity, J. Phys.: Conf. Ser. 286, 012017 (2011).

2010

- I.V. Proskurin and A. S. Ovchinnikov and J. Kishine, Field-like spin-transfer torque in a chiral helimagnet, JETP 138, 266 (2010).
- J. Kishine and A. S. Ovchinnikov and I.V. Proskurin, Sliding conductivity of a magnetic kink crystal in a chiral helimagnet, Phys. Rev. B 82, 064407 (2010).
- A.A. Bukharov and A.S. Ovchinnikov and N.V. Baranov and K. Inoue, Magnetic hysteresis and domain wall dynamics in single chain magnets with antiferromagnetic interchain coupling, Journal of Physics: Condensed Matter 22, 436003 (2010).
- J. Kishine and A. S. Ovchinnikov, Adiabatic and nonadiabatic spin-transfer torques in the current-driven magnetic domain wall motion, Phys. Rev. B 81, 134405 (2010)
- A. S. Ovchinnikov, I. G. Bostrem, and Vl. E. Sinitsyn, cluster perturbation theory for spin Hamiltonians, Theoretical and Mathematical Physics, 162(2): 179–187 (2010)
- I. G. Bostrem, V. E. Sinitsyn, A. S. Ovchinnikov, Y. Hosokoshi and K. Inoue, Bose–Einstein condensation of semi-hard bosons in the S = 1 dimerized organic compound F2PNNNO, J. Phys.: Condens. Matter 22 (2010), 036001

2009

- J. Kishine and A. S. Ovchinnikov, Theory of spin resonance in a chiral helimagnet, Phys. Rev. B 79, 220405(R) (2009).
- A. B. Borisov and J. Kishine and I.G. Bostrem and A.S. Ovchinnikov, Magnetic soliton transport over topological spin texture in chiral helimagnet with strong easy-plane anisotropy, Phys. Rev. B 79, 134436 (2009).
- A.A. Bukharov and A.S. Ovchinnikov and N.V. Baranov and K. Inoue, Magnetic hysteresis in a molecular Ising ferrimagnet: Glauber dynamics approach, Eur. Phys. J. B 70, 369 (2009).
- I. G. Bostrem and J. Kishine and R. V. Lavrov and A. S. Ovchinnikov, Hidden Galilean symmetry, conservation laws and emergence of spin current in the soliton sector of chiral helimagnet, Phys. Lett. A 373, 558 (2009)

2008

- R. Morgunov and M. V. Kirman and K. Inoue and Y. Tanimoto and J. Kishine and A. S. Ovchinnikov and O. Kazakova, Spin solitons and spin waves in chiral and racemic molecular based ferrimagnets, Phys. Rev. B 77, 184419 (2008)
- I. G. Bostrem and J. Kishine and A. S. Ovchinnikov, Theory of spin current in chiral helimagnets, Phys. Rev. B 78, 064425 (2008).
- I. G. Bostrem and J. Kishine and A. S. Ovchinnikov, Transport spin current driven by the moving kink crystal in a chiral helimagnet, Phys. Rev. B 77, 132405 (2008).