Negative spontaneous magnetization and semi-spin glass magnetic order in mixed spinel Co0.6Zn0.4Fe1.7Mn0.3O4

2015 ◽  
Vol 118 (13) ◽  
pp. 133902 ◽  
Author(s):  
Arti Gupta ◽  
R. P. Tandon ◽  
A. B. Shinde ◽  
P. S. R. Krishna ◽  
Ratnamala Chatterjee
Keyword(s):  
Spin Glass ◽  
Magnetic Order ◽  
Spontaneous Magnetization ◽  
Mixed Spinel

Investigation of Magnetic Order in Iron Oxide-Nickel Oxide Superlattices with Modulation Wavelength Less Than 80 Å

1991 ◽  
Vol 231 ◽  
Author(s):  
S. D. Berry ◽  
D. M. Lind ◽  
G. Chern ◽  
H. Mathias ◽  
L. R. Testardi
Keyword(s):  
Magnetic Order ◽  
Spontaneous Magnetization ◽  
X Ray Diffraction ◽  
High Crystalline Quality ◽  
X Ray ◽  
Long Wavelength ◽  
Saturation Moment ◽  
Very High ◽  
Modulation Wavelength

AbstractWe have investigated the magnetic order, using SQUID magnetometry, for short modulation wavelength Fe3O4/NiO superlattices, grown on single crystal MgO. Ferrimagnetic Fe3O4 has a saturation moment of ~500 emu/cm3 at 0 K and a Curie temperature of 858 K, while bulk NiO is antiferromagnetic with a NMel temperature of 525 K. Very high crystalline quality with little interdiffusion is indicated by X-ray diffraction, SEM, optical microscopy, and in-situ RHEED, and the samples show highly anisotropic electrical conductivity which also indicates the strong modulation present. Long wavelength samples (Amod > 200 Å) have a behavior only slightly different from that expected from bulk Fe3O4, but for Amod<80 Å, spontaneous magnetization is replaced by paramagnetism, with weak temperature dependence (not I/T) from 5 K to 400 K.

scholarly journals Influence of Crystallite Size on the Magnetic Order in Semiconducting ZnCr2Se4 Nanoparticles

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3947 ◽  
Author(s):  
Ewa Malicka ◽  
Małgorzata Karolus ◽  
Tadeusz Groń ◽  
Adrian Gudwański ◽  
Andrzej Ślebarski ◽  
...  
Keyword(s):  
Single Crystal ◽  
Specific Heat ◽  
Spin Glass ◽  
Crystallite Size ◽  
Magnetic Order ◽  
Ac Susceptibility ◽  
High Energy ◽  
Zero Field ◽  
Bulk Single Crystal ◽  
Field Cooling

Structural, electrical, magnetic, and specific heat measurements were carried out on ZnCr2Se4 single crystal and on nanocrystals obtained from the milling of this single crystal after 1, 3, and 5 h, whose crystallite sizes were 25.2, 2.5, and 2 nm, respectively. For this purpose, the high-energy ball-milling method was used. The above studies showed that all samples have a spinel structure, and are p-type semiconductors with less milling time and n-type with a higher one. In turn, the decrease in crystallite size caused a change in the magnetic order, from antiferromagnetic for bulk material and nanocrystals after 1 and 3 h of milling to spin-glass with the freezing temperature Tf = 20 K for the sample after 5 h of milling. The spin-glass behavior for this sample was derived from a broad peak of dc magnetic susceptibility, a splitting of the zero-field-cooling and field-cooling susceptibilities, and from the shift of Tf towards the higher frequency of the ac susceptibility curves. A spectacular result for this sample is also the lack of a peak on the specific heat curve, suggesting a disappearance of the structural transition that is observed for the bulk single crystal.

Coexistence of magnetic order and spin-glass-like phase in the pyrochlore antiferromagnet Na3Co(CO3)2Cl

2013 ◽  
Vol 87 (21) ◽  
Author(s):  
Zhendong Fu ◽  
Yanzhen Zheng ◽  
Yinguo Xiao ◽  
Subhankar Bedanta ◽  
Anatoliy Senyshyn ◽  
...  
Keyword(s):  
Spin Glass ◽  
Magnetic Order

scholarly journals Phase Transition Spin Glass-Long Magnetic Order in New Thiospinels Containing Cu, Cr and Sb

1997 ◽  
Vol 92 (2) ◽  
pp. 441-444
Author(s):  
L.I. Koroleva ◽  
R.V. Demin ◽  
M.Kh. Mashaev ◽  
D.A. Saiflullaeva ◽  
T.V. Virovets ◽  
...  
Keyword(s):  
Phase Transition ◽  
Spin Glass ◽  
Magnetic Order

Suppression of Spin-Glass State in PrB6

2012 ◽  
Vol 190 ◽  
pp. 221-224 ◽  
Author(s):  
M.A. Anisimov ◽  
A.V. Bogach ◽  
V.V. Glushkov ◽  
S.V. Demishev ◽  
N.A. Samarin ◽  
...  
Keyword(s):  
Magnetic Fields ◽  
Spin Glass ◽  
Single Crystals ◽  
Phase Formation ◽  
Spontaneous Magnetization ◽  
Initial State ◽  
High Quality ◽  
Wide Range ◽  
Comprehensive Study

The comprehensive study of transverse magnetoresistance (MR) and magnetization has been carried out on the high quality single crystals of PrB6 in the wide range of temperatures 2-40K and magnetic fields up to 80kOe. In order to estimate the role of boron vacancies in the formation of the new spin-glass (SG) phase detected by Alekseev et al. below 20K the experiments were carried out on the ordinary (initial state) and annealed single crystals of PrB6. The data obtained demonstrate the appearance of spontaneous magnetization below TSG21.3K with M~1.6 emu/mol for initial state and the absence of spontaneous magnetization for the annealed PrB6 samples. On the contrary, quite similar behavior of MR was detected for various samples of PrB6. Our results suggest the existence of the aggregated boron vacancies which provoke the new SG phase formation in PrB6 at TSG.

Spin Glassiness and Ferromagnetism in Disordered Ni-Mn Alloys

1982 ◽  
Vol 19 ◽  
Author(s):  
James S. Kouvel
Keyword(s):  
Spin Glass ◽  
Critical Field ◽  
Curie Point ◽  
Magnetic Measurements ◽  
Spontaneous Magnetization ◽  
Uniaxial Anisotropy ◽  
Hysteresis Loops ◽  
Initial Susceptibility ◽  
Unidirectional Anisotropy ◽  
Glass Properties

ABSTRACTFrom magnetic measurements, the alloy Ni78Mn22 is found to undergo a field-induced transition from spin glassiness to ferromagnetism at a critical field that decreases from ∼140 Oe to zero as the temperature is raised from 4.2 K to 40 K, the ferromagnetic Curie point being ∼270 K. The alloy Ni74Mn26 is found to transform at 80 K from a spin glass to a state of infinite initial susceptibility but no spontaneous magnetization and to remain so up to 155 K, where it becomes paramagnetic. The spin-glass properties of Ni78Mn22 below 40 K and of Ni74Mn26 below 80 K include displaced hysteresis loops produced by cooling in a field. The changes in the hysteresis loops upon subsequent warming correspond to a gradual conversion of a unidirectional anisotropy to a uniaxial anisotropy.

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