Macroscopic Quantum Tunneling in PdO Nanoparticles
Por:
Ascencio, Francisco, Reyes-Damian, C., ESCUDERO, ROBERTO
Publicada:
1 may 2021
Ahead of Print:
1 abr 2021
Resumen:
We studied the physical behavior of PdO nanoparticles at low
temperatures, which presents an unusual behavior clearly related to
macroscopic quantum tunneling. The samples show a tetragonal single
phase with P42/mmc space group. Most importantly, the particle size was
estimated at about 5.07 +/- 1.97 nm. Appropriate techniques were used to
determine the characteristic of these nanoparticles. The most important
aspect of this study is the magnetic characterization performed at low
temperatures. It shows a peak at 50 K in zero field cooling (ZFC) mode
that corresponds to the blocking temperature (T-B). These measurements
in ZFC and field cooling (FC) indicate that the peak behavior is due to
different relaxation times of the asymmetrical barriers when the
electron changes from a metastable state to another. Below T-B in FC
mode, the magnetization decreases with temperature until 36 K; this
temperature is the crossover temperature T-Cr related to the anisotropy
of the barriers, indicative of macroscopic quantum tunneling.
Filiaciones:
Ascencio, Francisco:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Mexico City 04510, DF, Mexico
Reyes-Damian, C.:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Mexico City 04510, DF, Mexico
ESCUDERO, ROBERTO:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Mexico City 04510, DF, Mexico
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