Spin Induced Quantum Tunneling of the Magnetization


YILDIZ G. D. , YILDIZ Y. G. , Sarli N.

SPIN, 2021 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası:
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1142/s2010324721500119
  • Dergi Adı: SPIN

Özet

Quantum tunneling of the magnetization (QTM) of the spin-1/2 Vanadium-15 (V15) single molecular magnets (SMMs) is investigated by means of the effective field theory developed by Kaneyoshi. We deal with the two hexagon layers (shell, VS) and one triangular interlayer (core, VC) with the spin-1/2 Ising particles. We find that the V15 has a normal ferromagnetic hysteresis behavior for its all spins are up (parallel). However, V15 has a staircase-like hysteresis behavior that is the signature of the QTM for the spin-down orientation (antiparallel) of the core. QTM appears with the splitting of the magnetizations versus temperature (M-T) and external field (M-H) curves. Namely, QTM occurs from +m(VC1) to -m(VC2)(|m(VC1)|>|m(VC2)|) in the core, from +m(VS1) to +m(VS2) (|m(VS1)|>|m(VS2)|) in the shell (only mVS-H curves at T> 0.1) and from +M1(V15) to +M2(V15) (|M1V15|>|M2V15|) in the total V15. By considering these different splitting behaviors of the magnetizations of the shell, core and total V15 at TT-C, we suggest three different kinds of QTM: 1-ferromagnetic QTM (FMQTM) at TT-C for the shell, core and total V15 SMM. Moreover, it is found that there is a relationship between the QTM and type II and surface superconductivity. The EFT results of QTM in V15 are in good agreement with the other theoretical and experimental results of the V15 and other SMMs.