| Autor: |
Rigoni, Carlo, Beaune, Grégory, Harnist, Bent, Sohrabi, Fereshteh, Timonen, Jaakko V.I. |
| Přispěvatelé: |
Active Matter, Department of Applied Physics, Aalto-yliopisto, Aalto University |
| Jazyk: |
angličtina |
| Zdroj: |
Communications Materials. 3(1) |
| ISSN: |
2662-4443 |
| DOI: |
10.1038/s43246-022-00249-z |
| Popis: |
openaire: EC/H2020/803937/EU//InterActive Funding Information: J.V.I.T. acknowledges funding from ERC (803937) and Academy of Finland (316219). We acknowledge the facilities and technical support by Aalto University at OtaNano Nanomicroscopy Centre (Aalto-NMC). Publisher Copyright: © 2022, The Author(s). Ferrofluids are magnetic liquids known for the patterns they form in external magnetic fields. Typically, the patterns form at the interface between a ferrofluid and another immiscible non-magnetic fluid with a large interfacial tension γ ∼ 10−2 N m−1, leading to large pattern periodicities. Here we show that it is possible to reduce the interfacial tension several orders of magnitude down to ca. γ ∼ 10−6 N m−1 by using two immiscible aqueous phases based on spontaneous phase separation of dextran and polyethylene glycol and the asymmetric partitioning of superparamagnetic maghemite nanoparticles into the dextran-rich phase. The system exhibits classic Rosensweig instability in a uniform magnetic field with a periodicity of ∼200 μm, significantly lower than in traditional systems (∼10 mm). This system paves the way towards the science of pattern formation at the limit of vanishing interfacial tension and ferrofluid applications driven by small external magnetic fields. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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