From Superparamagnetism to Macroscopic Quantum Tunneling with Individual Nanostructures of SrRuO3

Speaker
Omer Sinwani, Bar-Ilan
Date
03/04/2014 - 16:30 - 15:30Add to Calendar 2014-04-03 15:30:00 2014-04-03 16:30:00 From Superparamagnetism to Macroscopic Quantum Tunneling with Individual Nanostructures of SrRuO3 The interest in magnetization reversal in nanostructures mainly focuses on two phenomena: the superparamagnetic behavior at a temperature range below the Curie temperature and the expected crossover between thermally-activated reversal to reversal dominated by macroscopic quantum tunneling at sufficiently low temperatures. Here we explore both phenomena by monitoring individual reversals in nanostructures of SrRuO3 and obtain novel insight of both phenomena. In particular, we show for the first time the applicability of the Langevin equation to superparamagnetic fluctuations of an individual volume [1] and we find compelling indication for magnetization reversal dominated by macroscopic quantum tunneling below a record high temperature of  10 K [2].   References O. Sinwani, J. W. Reiner, and L. Klein (2014). Monitoring superparamagnetic Langevin behavior of individual SrRuO3 nanostructures. Phys. Rev. B 89 020404(R). O. Sinwani, J. W. Reiner, and L. Klein (2012). Indication for macroscopic quantum tunneling below 10 K in nanostructures of SrRuO3. Phys. Rev. B 86 100403(R). Resnick Building 209, room 210 המחלקה לפיזיקה physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
Resnick Building 209, room 210
Abstract

The interest in magnetization reversal in nanostructures mainly focuses on two phenomena: the superparamagnetic behavior at a temperature range below the Curie temperature and the expected crossover between thermally-activated reversal to reversal dominated by macroscopic quantum tunneling at sufficiently low temperatures. Here we explore both phenomena by monitoring individual reversals in nanostructures of SrRuO3 and obtain novel insight of both phenomena. In particular, we show for the first time the applicability of the Langevin equation to superparamagnetic fluctuations of an individual volume [1] and we find compelling indication for magnetization reversal dominated by macroscopic quantum tunneling below a record high temperature of  10 K [2].

 

References

  1. O. Sinwani, J. W. Reiner, and L. Klein (2014). Monitoring superparamagnetic Langevin behavior of individual SrRuO3 nanostructures. Phys. Rev. B 89 020404(R).
  2. O. Sinwani, J. W. Reiner, and L. Klein (2012). Indication for macroscopic quantum tunneling below 10 K in nanostructures of SrRuO3. Phys. Rev. B 86 100403(R).

תאריך עדכון אחרון : 03/03/2014