Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> Nanoparticles
A series of GdCu<inline-formula> <math display="inline"> <semantics> <msub> <mrow></mrow> <mn>2</mn> </msub> </semantics> </math> </inline-formula> nanoparticles with controlled sizes ranging from 7 nm to 40 nm has bee...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-06-01
|
| Series: | Nanomaterials |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2079-4991/10/6/1117 |
| _version_ | 1797566021114003456 |
|---|---|
| author | E. M. Jefremovas J. Alonso M. de la Fuente Rodríguez J. Rodríguez Fernández J. I. Espeso D. P. Rojas A. García-Prieto M. L. Fernández-Gubieda L. Fernández Barquín |
| author_facet | E. M. Jefremovas J. Alonso M. de la Fuente Rodríguez J. Rodríguez Fernández J. I. Espeso D. P. Rojas A. García-Prieto M. L. Fernández-Gubieda L. Fernández Barquín |
| author_sort | E. M. Jefremovas |
| collection | DOAJ |
| description | A series of GdCu<inline-formula> <math display="inline"> <semantics> <msub> <mrow></mrow> <mn>2</mn> </msub> </semantics> </math> </inline-formula> nanoparticles with controlled sizes ranging from 7 nm to 40 nm has been produced via high-energy inert-gas ball milling. Rietveld refinements on the X-ray diffraction measurements ensure that the bulk crystalline <inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mi>m</mi> <mi>m</mi> <mi>a</mi> </mrow> </semantics> </math> </inline-formula> structure is retained within the nanoparticles, thanks to the employed low milling times ranging from <i>t</i> = 0.5 to <i>t</i> = 5 h. The analysis of the magnetic measurements shows a crossover from Superantiferromagnetism (SAF) to a Super Spin Glass state as the size decreases at NP size of <inline-formula> <math display="inline"> <semantics> <mrow> <mo>〈</mo> <mi>D</mi> <mo>〉</mo> <mo>≈</mo> </mrow> </semantics> </math> </inline-formula> 18 nm. The microstrain contribution, which is always kept below 1%, together with the increasing surface-to-core ratio of the magnetic moments, trigger the magnetic disorder. Additionally, an extra contribution to the magnetic disorder is revealed within the SAF state, as the oscillating RKKY indirect exchange achieves to couple with the aforementioned contribution that emerges from the size reduction. The combination of both sources of disorder leads to a maximised frustration for <inline-formula> <math display="inline"> <semantics> <mrow> <mo>〈</mo> <mi>D</mi> <mo>〉</mo> <mo>≈</mo> </mrow> </semantics> </math> </inline-formula> 25 nm sized NPs. |
| first_indexed | 2024-03-10T19:20:57Z |
| format | Article |
| id | doaj.art-7d7c6df48f6b4fe7a85782bba2c6ac39 |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-03-10T19:20:57Z |
| publishDate | 2020-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Nanomaterials |
| spelling | doaj.art-7d7c6df48f6b4fe7a85782bba2c6ac392023-11-20T02:57:34ZengMDPI AGNanomaterials2079-49912020-06-01106111710.3390/nano10061117Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> NanoparticlesE. M. Jefremovas0J. Alonso1M. de la Fuente Rodríguez2J. Rodríguez Fernández3J. I. Espeso4D. P. Rojas5A. García-Prieto6M. L. Fernández-Gubieda7L. Fernández Barquín8Dpto. CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, SpainDpto. CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, SpainDpto. CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, SpainDpto. CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, SpainDpto. CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, SpainDpto. Estructuras y Física de la Edificación, ETSAM, Universidad Politécnica de Madrid, 28040 Madrid, SpainDpto. de Física Aplicada I, Escuela de Ingeniería de Bilbao, 48013 Bilbao, SpainDpto. de Electricidad y Electrónica, Universidad del País Vasco—UPV/EHU, 48940 Leioa, SpainDpto. CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander, SpainA series of GdCu<inline-formula> <math display="inline"> <semantics> <msub> <mrow></mrow> <mn>2</mn> </msub> </semantics> </math> </inline-formula> nanoparticles with controlled sizes ranging from 7 nm to 40 nm has been produced via high-energy inert-gas ball milling. Rietveld refinements on the X-ray diffraction measurements ensure that the bulk crystalline <inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mi>m</mi> <mi>m</mi> <mi>a</mi> </mrow> </semantics> </math> </inline-formula> structure is retained within the nanoparticles, thanks to the employed low milling times ranging from <i>t</i> = 0.5 to <i>t</i> = 5 h. The analysis of the magnetic measurements shows a crossover from Superantiferromagnetism (SAF) to a Super Spin Glass state as the size decreases at NP size of <inline-formula> <math display="inline"> <semantics> <mrow> <mo>〈</mo> <mi>D</mi> <mo>〉</mo> <mo>≈</mo> </mrow> </semantics> </math> </inline-formula> 18 nm. The microstrain contribution, which is always kept below 1%, together with the increasing surface-to-core ratio of the magnetic moments, trigger the magnetic disorder. Additionally, an extra contribution to the magnetic disorder is revealed within the SAF state, as the oscillating RKKY indirect exchange achieves to couple with the aforementioned contribution that emerges from the size reduction. The combination of both sources of disorder leads to a maximised frustration for <inline-formula> <math display="inline"> <semantics> <mrow> <mo>〈</mo> <mi>D</mi> <mo>〉</mo> <mo>≈</mo> </mrow> </semantics> </math> </inline-formula> 25 nm sized NPs.https://www.mdpi.com/2079-4991/10/6/1117magnetic nanoparticlesrare earth intermetallicsmagnetic couplingX-ray diffractionSpin Glass |
| spellingShingle | E. M. Jefremovas J. Alonso M. de la Fuente Rodríguez J. Rodríguez Fernández J. I. Espeso D. P. Rojas A. García-Prieto M. L. Fernández-Gubieda L. Fernández Barquín Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> Nanoparticles Nanomaterials magnetic nanoparticles rare earth intermetallics magnetic coupling X-ray diffraction Spin Glass |
| title | Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> Nanoparticles |
| title_full | Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> Nanoparticles |
| title_fullStr | Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> Nanoparticles |
| title_full_unstemmed | Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> Nanoparticles |
| title_short | Investigating the Size and Microstrain Influence in the Magnetic Order/Disorder State of GdCu<sub>2</sub> Nanoparticles |
| title_sort | investigating the size and microstrain influence in the magnetic order disorder state of gdcu sub 2 sub nanoparticles |
| topic | magnetic nanoparticles rare earth intermetallics magnetic coupling X-ray diffraction Spin Glass |
| url | https://www.mdpi.com/2079-4991/10/6/1117 |
| work_keys_str_mv | AT emjefremovas investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT jalonso investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT mdelafuenterodriguez investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT jrodriguezfernandez investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT jiespeso investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT dprojas investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT agarciaprieto investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT mlfernandezgubieda investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles AT lfernandezbarquin investigatingthesizeandmicrostraininfluenceinthemagneticorderdisorderstateofgdcusub2subnanoparticles |