Ultrafast demagnetization

Imaging Ultrafast Demagnetization Dynamics after a Spatially Localized Optical Excitation.
C. von Korff Schmising, B. Pfau, M. Schneider, C. M. Günther, M. Giovannella, J. Perron, B. Vodungbo, L. Müller, F. Capotondi, E. Pedersoli, N. Mahne, J. Lüning, and S. Eisebitt
Phys. Rev.Lett.11, 217203 (2014)

Zero modes in magnetic systems

Zero modes in magnetic systems: General theory and an efficient computational scheme.

F. J. Buijnsters, A. Fasolino, and M. I. Katsnelson

Phys. Rev. B 89, 174433 (2014)

Quantum spin ice. Reviews

Quantum spin ice: a search for gapless quantum spin liquids in pyrochlore magnets.

M J P Gingras and P A McClarty
Rep. Prog. Phys. 77, 056501 (2014)


Monte Carlo studies of the dipolar spin ice model
Roger G Melko and Michel J P Gingras J. Phys.: Condens. Matter 16, R1277 (2014)

Skyrmions in FePt layers

Skyrmion magnetic structure of an ordered FePt monolayer deposited on Pt(111).
S. Polesya, S. Mankovsky, S. Bornemann, D. Ködderitzsch,1 J. Minár, and H. Ebert

Phys. Rev. B 89, 184414 (2014)

Magnetic moment distribution within the Skyrmion. Yellow and blue colors in (a) represent schematically the region giving gain and loss of Zeeman energy in the presence of a magnetic field; blue color in (b) shows the region giving loss of the exchange energy contributed by in-plane components of magnetic moments. (c) and (d): Structure of single Sk obtained with the contributions of the Fe-Pt exchange interactions taken into account [the same color code as in (a) and (b)].

Effects of dimensionality and spatial distribution on the magnetic relaxation of interacting ferromagnetic nanoclusters: A Monte Carlo study

Effects of dimensionality and spatial distribution on the magnetic relaxation of interacting ferromagnetic nanoclusters: A Monte Carlo study.
D. Brinis, A. Laggoun, D. Ledue and  R. Patte

J. Appl. Phys. 115, 173906 (2014)

χ ac /χ0 vs T for the xy-square lattice with various strengths of the DI (f = 10⁴ Hz). (a) χ′ and (b) χ″.

Amazing physics of magnetized chains of beads

Magnetic ghosts and monopoles. N Vandewalle and S Dorbolo 2014

New J. Phys. 16, 013050 (2014)

The magneto-elastica: from self-buckling to self-assembly.
Dominic Vella, Emmanuel du Pontavice,  Cameron L. Hall and Alain Goriely

Proc. Royal Soc. A 470 20130609 (2013)

Three simple experiments that illustrate the resistance to deformation of assemblies of ferromagnetic spheres. (a) The self-buckling of a vertical chain of magnetic spheres as further spheres are added. (b) The prolate–oblate oscillation of a ring of magnetic spheres. Snap-shots of the motion are shown at intervals of 0.021 s. (c) A self-assembled chiral ‘nano-tube’. In each case, the diameter of the spheres is 2a=5 mm and the magnetic field strength is B= 1.195 T.

Collective dynamics of 2D ferromegnetic element arrays

Review: Magneto.optical measurements of collective spin dynamics of two-dimensional arrays of ferromagnetic elements.
Bivas Rana and Anjan Barman
Spin 3, 1330001(2013) 

(a) Simulated resonant modes for an array of 200nm square dots with 100nm interdot separations are plotted as a
function of the azimuthal angle ( ) of the bias field. (b) Powerand phase distributions of the simulated modes are shown for
four di®erent values of . The color scales are shown at the top right corner of the figure.

New route to nanocrystal synthesis: galvanic replacement

All change for nanocrystals.
Maria Ibáñez and Andreu Cabot
Science 340, 935 (2013)

Galvanic Replacement Reactions in Metal Oxide Nanocrystals.
Myoung Hwan Oh, Taekyung Yu, Seung-Ho Yu, Byungkwon Lim, Kyung-Tae Ko,Marc-Georg Willinger, Dong-Hwa Seo, Byung Hyo Kim, Min Gee Cho, Jae-Hoon Park, Kisuk Kang, Yung-Eun Sung, Nicola Pinna, Taeghwan Hyeon
Science 340, 964 (2013)

Schematic illustration of the transformation of Mn3O4 NCs, showing the evolution of their morphology via the localized dissolution of Mn3O4 and the surface precipitation of g-Fe2O3. (B to E) HRTEM images of the hollow nanostructures synthesized by the reaction of Mn3O4 NCs with 1 ml of aqueous solutions of iron(II) perchlorate having different concentrations.

Superantiferromagnetism in NPs

Size-induced superantiferromagnetism with reentrant spin-glass behavior in metallic nanoparticles of TbCu2.
C. Echevarria-Bonet, D. P. Rojas, J. I. Espeso, J. Rodríguez Fernández,1 L. Rodríguez Fernández, P. Gorria, J. A. Blanco, M. L. Fdez-Gubieda, E. Bauer, G. André, and L. Fernández Barquín
Phys. Rev. B 87, 180407 (2013)

Thermomagnetic DC-susceptibility ZFC curves obtained with magnetic fields, 1 kOe H 10 kOe, where
the evolution from AF to SG state can be observed. A FC curve is also plotted at H = 1 kOe to evidence the irreversibility. Inset (bottom): Linear Tf variation vs H2/3. Inset (top): ZFC DC susceptibility of the alloy at a pressure P = 1.1 GPa.

Topological flat bands in dipolar spins

Topological Flat Bands from Dipolar Spin Systems
N.Y. Yao, C. R. Laumann, A.V. Gorshkov, S. D. Bennett, E. Demler, P. Zoller, and M. D. Lukin
Phys. Rev. Lett. 109, 266804 (2012)

Schematic representation of a 2D dipolar droplet. The grey droplet represents a 2D array of interacting tilted dipoles. The dipoles are tilted by a static field in the ^z direction, oriented at 0, 0 relative to the lattice basis fX; Y; Zg.Rij is a vector connecting dipoles in the XY plane.

TEM observation of AFM in NiO

Antiferromagnetism in NiO Observed by Transmission Electron Diffraction.
J. C. Loudon
Phys. Rev Lett. 109, 267204 (2012)

(a) Electron diffraction pattern from the [112] zone axis taken at room temperature from a region of diameter 880 nm
with an exposure of 70 s. The +-1/2[111] superlattice are indicated by arrows. (b) Electron diffraction pattern from the same region taken at 563 K, above the Ne´el temperature TN ¼ 523 K, showing that the superlattice reflections are no longer present.

Interplay between interation and morphology in NP assemblies

Magnetic behavior of dense nanoparticle assemblies: Interplay of interparticle interactions and particle system morphology.
G. Margaris, K. N. Trohidou, V. Iannotti, G. Ausanio, L. Lanotte, and D. Fiorani
Phys. Rev. B 86, 214425 (2012)

Assembly of NPs interacting with three different dipolar interaction strengths (assembly concentration p = 0.5). (a) Initial
magnetization vs H curves (VC) at temperature t = 0.005 and (b) ZFC/FC magnetization vs T curves with hcool = 0.05.

Self assembly of magnetoferritin NPs

Hierarchical Self-Assembly and Optical Disassembly for Controlled Switching of Magnetoferritin Nanoparticle Magnetism.
Mauri A. Kostiainen,Pierpaolo Ceci,Manuela Fornara, Panu Hiekkataipale, Oksana Kasyutich, Roeland J. M. Nolte, Jeroen J. L. M. Cornelissen, Ryan D. Desautels, and Johan van Lierop
ACS Nano 5, 6394 (2011)

Protein cages such as ferritin and viral capsids are interesting building blocks for nanotechnology due to their monodisperse structure and ability to encapsulate various functional moieties. Here we show that recombinant ferritin protein cages encapsulating Fe₃O₄–γ-Fe₂O₃ iron oxide (magnetoferritin) nanoparticles and photodegradable Newkome-type dendrons self-assemble into micrometer-sized complexes with a face-centered-cubic (fcc) superstructure and a lattice constant of 13.1 nm.

Binary nanoparticle superlattices

Electrostatic assembly of binary nanoparticle superlattices using protein cages.
Mauri A. Kostiainen, Panu Hiekkataipale, Ari Laiho, Vincent Lemieux, Jani Seitsonen, Janne Ruokolainen and Pierpaolo Ceci
Nature Nanotechnology 8, 52 (2013)

a, Native CCMV with RNA genome inside. b, Apoferritin and magnetoferritin (recombinant ferritin cage from Pyrococcus furiosus encapsulating Fe₃O₄–γ-Fe₂O₃). c, Gold nanoparticle stabilized with an amphiphilic ligand featuring a cationic quaternary amine end-group. d, Size of the building blocks drawn to scale.

Review of Iron oxide NPs for medical applications

Chemical Design of Biocompatible Iron Oxide Nanoparticles for Medical Applications.
Daishun Ling and Taeghwan Hyeon
Small, ASAP (2012)

Magnetic nanoparticles in biosciences: review

Magnetic Nanoparticles and Biosciences
Ivo Safaric and Mirka Safarikova
Monatschefte Für Chemie 133, 737 (2002)

Electron micrograph of a Magnetospirillum cell with magnetosomes arranged in a chain.

Assymetric hysteresis loops in EB core/shell NPs

Asymmetric hysteresis loops and its dependence on magnetic anisotropy in exchange biased Co/CoO core-shell nanoparticles.
Sayan Chandra, Hafsa Khurshid, Manh-Huong Phan, and Hariharan Srikanth
Appl. Phys. Lett. 101, 232405 (2012)

(a) and (b) Bipolar TS scan at 20K and 130K under FC condition indicatingthe anisotropy fields and g, (c) temperature dependence of g, (d) temperature dependence of shift in the first anisotropy peaks in the bipolar scans.

Thermoelectric SW detection

Thermoelectric Detection of SpinWaves.
H. Schultheiss, J. E. Pearson, S. D. Bader, and A. Hoffmann
Phys. Rev. Lett. 109, 237204 (2012)

(a), (b) Schematic of the sample. The spin-wave waveguide is 2 mm long, 20 m wide, and made from 100 nm thick Permalloy on a GaAs substrate. The coplanar waveguide for rf excitation and the leads for dc voltage measurements are made from 150 nm thick Au. The CPW has a signal linewidth of 10 m and a signal-to-ground-line separation of 5 m. (c) Illustration of the z distribution of the dissipated power and resulting temperature profile.

Plasmonics

Special about Plasmonics in Nanture Photonics
Nature Photonics Volume 6 No 11 pp707-794 (2012)

Heat dissipation in NP assemblies

Ferromagnetism, hysteresis and enhanced heat dissipation in assemblies of superparamagnetic nanoparticles.
Vanchna Singh and Varsha Banerjee
J.Appl. Phys. 112, 114912 (2012)

Typical hysteresis loops corresponding to 10 nm diameter magnetite particles for increasing values of N, the number of particles/cc. The inset shows M=Ms for the two lower concentrations to clarify the deviation from the Langevin response (for N ¼ 1010) to the emergence of hysteresis loops with increasing concentrations (interactions).

Canted AFM in hollow nanospheres

Canted antiferromagnetism on a nanodimensional spherical surface geometry: The case of MnCO3 small hollow nanospheres.
Jin Bae Lee, Won G. Hong, Hae Jin Kim, Z. Jaglicic, S. Jazbec, M. Wencka, A. Jelen, and J. Dolinsek

Phys. Rev. B 86, 224407 (2012)

(a) The M(H) curves of the HNSs sample and the MnCO3 bulk at T = 5 K for the magnetic field sweep ±50 kOe. The inset shows the hysteresis curves on an expanded scale around the H = 0 origin. (b) The M − χAFMH curves, by subtracting the linear (AFM-type) contribution from the measured magnetization data. Away from the hysteretic region, only the curves of the up-field run are shown. The inset shows the pure FM hysteresis loops MFM(H) on an expanded scale.

Thermoelectric coating

Spin-current-driven thermoelectric coating.
Akihiro Kirihara, Ken-ichi Uchida, Yosuke Kajiwara, Masahiko Ishida, Yasunobu Nakamura,Takashi Manako, Eiji Saitoh and Shinichi Yorozu
Nature Materials 11,686 (2012)

Concept of the STE coating. a, Conventional TE generation method based on the Seebeck effect. The TE device contains a number of thermocouples (TCs), electrically connected in series, to obtain reasonable output voltage. The TE device is usually attached externally to heat sources, which apply the temperature difference across it. b, STE coating based on the SSE. The STE coating exhibits a straightforward scaling: a larger film area leads to a larger TE output. Such a simple film structure can be directly coated onto heat sources with different shaped (curved or uneven) surfaces.