TY - JOUR
T1 - Detection of an Anomalous Magnetic Transition in Hematite by Means of Derivative Microwave Absorption
AU - Alvarez, G.
AU - Montiel, H.
AU - Conde-Gallardo, A.
AU - Zamorano, R.
N1 - Publisher Copyright:
© 2015, Springer Science+Business Media New York.
PY - 2015/9/8
Y1 - 2015/9/8
N2 - We have investigated the derivative microwave power absorption (dP/dH) at X-band (8.8–9.8 GHz) in the hematite (a-Fe2O3) powders, for the 180-280 K temperature range. Two microwave absorption techniques are mainly used: the magnetically modulated microwave absorption spectroscopy (MAMMAS) and the extended field microwave absorption (EFMA). MAMMAS response showed distinctive features associated with the Morin transition at TMo = 260 K, and below TMo, a weak ferromagnetism is also observed. Additionally, EFMA technique is used to give further knowledge on this material, where this technique shows a change in microwave absorption dynamics in the vicinity of 200 K and it is associated with an anomalous magnetic transition, different to the Morin transition, and which is also confirmed by means of magnetic measurements and the low-field microwave absorption (LFMA).
AB - We have investigated the derivative microwave power absorption (dP/dH) at X-band (8.8–9.8 GHz) in the hematite (a-Fe2O3) powders, for the 180-280 K temperature range. Two microwave absorption techniques are mainly used: the magnetically modulated microwave absorption spectroscopy (MAMMAS) and the extended field microwave absorption (EFMA). MAMMAS response showed distinctive features associated with the Morin transition at TMo = 260 K, and below TMo, a weak ferromagnetism is also observed. Additionally, EFMA technique is used to give further knowledge on this material, where this technique shows a change in microwave absorption dynamics in the vicinity of 200 K and it is associated with an anomalous magnetic transition, different to the Morin transition, and which is also confirmed by means of magnetic measurements and the low-field microwave absorption (LFMA).
KW - Derivative microwave absorption
KW - Hematite
KW - Magnetic transitions
UR - http://www.scopus.com/inward/record.url?scp=84938743160&partnerID=8YFLogxK
U2 - 10.1007/s10948-015-3085-7
DO - 10.1007/s10948-015-3085-7
M3 - Artículo
SN - 1557-1939
VL - 28
SP - 2731
EP - 2734
JO - Journal of Superconductivity and Novel Magnetism
JF - Journal of Superconductivity and Novel Magnetism
IS - 9
ER -