Quantum Einstein-de Haas effect

Quantum Einstein-de Haas effect.
Marc Ganzhorn, Svetlana Klyatskaya, Mario Ruben; Wolfgang Wernsdorfer
Nature Communications 7, 11443 (2016)

Molecules at the Quantum–Classical Nanoparticle Interface

Molecules at the Quantum–Classical Nanoparticle Interface: Giant Mn70 Single-Molecule Magnets of ∼4 nm Diameter.

Alina Vinslava, Anastasios J. Tasiopoulos, Wolfgang Wernsdorfer, Khalil A. Abboud, and George Christou

Inorganic Chemistry 55, 3419 (2016)

 

Classical and quantum dynamics of molecular spins on graphene

The classical and quantum dynamics of molecular spins on graphene.

Christian Cervetti, Angelo Rettori, Maria Gloria Pini, Andrea Cornia, Ana Repollés, Fernando Luis, Martin Dressel, Stephan Rauschenbach, Klaus Kern, Marko Burghard, Lapo Bogani

Nature Materials 15, 164 (2016)

a, |m_s sublevels of the ground state of the single-molecule-magnet [Fe₄(L)₂(dpm)₆], as obtained from equation (1). Absorption of phonons allows the barrier to be thermically overcome (green arrows). W ± n indicate the transition probabilities between magnetic |m states induced by the absorption (+) or emission (−) of n phonons. Quantum tunnelling happens between admixed levels (red arrows), whereas hyperfine and dipolar interactions create energy distributions (orange). Interaction with Dirac electrons increases the tunnel splittings below |3 and |−3 (red areas, exaggerated for clarity). b, Temperature and frequency dependence of the imaginary component of the dynamic susceptibility (χ′′) in a magnetic field H = 1 kOe for [Fe₄(L)₂(dpm)₆] (top) and hybrids with isolated molecules (bottom). Lines are simulations with the theory (see text for the theory). c, Temperature and frequency dependence of the real component of the dynamic susceptibility (χ′) in H = 0 for [Fe₄(L)₂(dpm)₆] (top) and hybrids with isolated molecules (bottom). Lines are simulations with the theory (see text for the theory).

Exchange bias in molecular layers

Exchange bias and room-temperature magnetic order in molecular layers.

Manuel Gruber, Fatima Ibrahim, Samy Boukari, Hironari Isshiki, Loïc Joly, Moritz Peter, Michał Studniarek, Victor Da Costa, Hashim Jabbar, Vincent Davesne, Ufuk Halisdemir, Jinjie Chen, Jacek Arabski, Edwige Otero, Fadi Choueikani, Kai Chen, Philippe Ohresser, Wulf Wulfhekel, Fabrice Scheurer, Wolfgang Weber, Mebarek Alouani, Eric Beaurepaire & Martin Bowen

Nature Materials 14, 981 (2015)

Adsorption geometry and magnetic properties of the MnPc stacking on Co deduced from DFT calculations.

 

EB in molecular layers

Exchange bias and room-temperature magnetic order in molecular layers.

Manuel Gruber, Fatima Ibrahim, Samy Boukari, Hironari Isshiki, Loïc Joly, Moritz Peter, Michał Studniarek, Victor Da Costa, Hashim Jabbar, Vincent Davesne, Ufuk Halisdemir, Jinjie Chen, Jacek Arabski, Edwige Otero, Fadi Choueikani, Kai Chen, Philippe Ohresser, Wulf Wulfhekel, Fabrice Scheurer, Wolfgang Weber, Mebarek Alouani, Eric Beaurepaire, Martin Bowen

Nature Materials 14, 981 (2015)

The red arrows represent the orientation of the spin moments. Note that the third layer dominantly exhibits a paramagnetic behaviour. The left inset represents the second-ML molecule on top of the semi-transparent first-ML molecule. The right inset shows the relative alignment of the second-ML molecule (semi-transparent) to the third-ML molecule.

Molecular Nanomagnets and Magnetic Nanoparticles: A Review

Exploring the No-Man s Land between Molecular Nanomagnets and Magnetic Nanoparticles.
Dante Gatteschi, Maria Fittipaldi, Claudio Sangregorio, and Lorenzo Sorace
Angew. Chem. Int. Ed. 51, 4792 (2012)

That's about the size of it: A comparison of structural and magnetic properties of iron oxo based molecular nanomagnets (see picture, right) and magnetic nanoparticles (left) gives a deeper understanding of the magnetic behavior at the intermediate scale between molecular and bulk objects.

Realization of transverse-field Ising ferromagnet in molecular cluster

Transverse field Ising ferromagnetism in Mn12-acetate-MeOH.
P. Subedi, A. D. Kent, Bo Wen, M. P. Sarachik, Y. Yeshurun, A. J. Millis, S. Mukherjee, and G. Christou
Phys. Rev. B 85, 134441 (2012)

The change in inverse susceptibility normalized to the susceptibility at zero field versus H2⊥ for Mn12-ac-
MeOH (green dots, open circle Ref. 21) and Mn12-ac (red squares, half filled, and solid squares are sample A and B in Ref. 16) at T = 3.2 K. The red dashed line is calculated using the random-field model of Ref. 16 (RFIFM) for the root-mean-square tilt angle of 1.8◦. The solid green line shows the result for the case with no tilt angle (TFIFM).

Single chain magnets as realization of 1D Ising and Heisenberg chains

A Stable Hybrid Bisphosphonate Polyoxometalate Single-Molecule MagnetHitoshi Miyasaka, Tomokura Madanbashi, Ayumi Saitoh, Natsuko Motokawa, Ryuta Ishikawa, Masahiro Yamashita, Stefan Bahr, Wolfgang Wernsdorfer, and Rodolphe Cl érac
Chemistry Eur. Journal 18, 3942 (2012)

A new functionalizable polyoxometalate platform: The heptanuclear Co^II polyoxometalate complex [{(B-α- PW₉O₃₄)Co₃(OH)(H₂O)₂(O₃PC(O)- (C₃H₆NH₃)PO₃)}₂Co]¹⁴⁻ represents a unique example of a magnetic, stable, functionalizable polyoxotungstate platform, and behaves as a single-molecule magnet.

Quantum magnetism of individual Mn12 cluster

The Quantum Magnetism of Individual Manganese-12-Acetate Molecular Magnets Anchored at Surfaces
Steffen Kahle, Zhitao Deng, Nikola Malinowski, Charlène Tonnoir, Alicia Forment-Aliaga, Nicha Thontasen, Gordon Rinke, Duy Le, Volodymyr Turkowski, Talat S. Rahman,Stephan Rauschenbach, Markus Ternes, and Klaus Kern
Nano Letters 12, 518 (2012)

Here we demonstrate that electrospray ion beam deposition facilitates grafting of intact Mn₁₂ molecules on metal as well as ultrathin insulating surfaces enabling submolecular resolution imaging by scanning tunneling microscopy. Using scanning tunneling spectroscopy we detect spin excitations from the magnetic ground state of the molecule at an ultrathin boron nitride decoupling layer. Our results are supported by density functional theory based calculations and establish that individual Mn₁₂ molecules retain their intrinsic spin on a well chosen solid support.

Molecular magnet networks in all dimensions

Dimensionality Selection in a Molecule-Based Magnet.
Paul A. Goddard, Jamie L. Manson, John Singleton, Isabel Franke,1 Tom Lancaster, Andrew J. Steele,Stephen J. Blundell, Christopher Baines, Francis L. Pratt, Ross D. McDonald, Oscar E. Ayala-Valenzuela,Jordan F. Corbey, Heather I. Southerland, Pinaki Sengupta, and John A. Schlueter
Phys. Rev. Lett. 108, 077208 (2012)

(a) Normalized pulsed-field magnetization of planar (T = 1.5 K), and chainlike  (T =0:5 K) Mn12 compunds. (b) The results of QMC simulations of the low-temperature magnetization for 3D  2D and 1D AF. The lines are the pulsed-field data scaled by the saturation field (Bc). (c) The relation between the exchange anisotropy and the ratio of critical temperature and primaryexchange energy in Q1D and Q2D antiferromagnets deduced from QMC simulations (d) Anisotropy of the g factor in the planar and (e) chainlike compounds measured using ESR at 10 K and 1.5 K, respectively.

MQT in trigonal molecule magnets

Quantum tunneling of magnetization in trigonal single-molecule magnets.
Junjie Liu, Enrique del Barco, and Stephen Hill
Phys. Rev. B 85, 012406 (2012)

Zeeman diagram for a spin S =6 multiplet with easy-axis anisotropy [D<0 in Eq. (1)] and H//z. All possible nonzero tunneling gaps for C3 symmetry are labeled according to the scheme discussed in the main text. The inset shows the HT
dependence of the odd-n tunneling gaps.

Quantum deflagration in molecular magnets

Quantum deflagration and supersonic fronts of tunneling in molecular magnets.
D. A. Garanin and Saaber Shoyeb
ArXiv 1112.5171 (2011)

Spatial profiles of the deflagration front in a small transverse field, B? = 0:05 T at the peak of the front speed at Bz = 2:852 T. There is a resonance spin tunneling at the face of the front and burning in its central and rear parts.

Exchanged biased molecular clusters

A Supramolecular Aggregate of Four Exchange-Biased Single-Molecule Magnets.
Tu N. Nguyen, Wolfgang Wernsdorfer,  Khalil A. Abboud, and George Christou
JACS 133, 20688 (2011)

Hysteresis loops in plots of magnetization vs dc field for a single crystal of 3·xCH2Cl2 (top) at the indicated temperatures at 0.28 T/s and (bottom) at the indicated field scan rates at 0.04 K. M is normalized to its saturation value, MS.

Manipulating molecular magnets by Landau-Zener

Manipulation of the spin in single molecule magnets via Landau-Zener transitions
Andrew Palii, Boris Tsukerblat, Juan M. Clemente-Juan, Alejandro Gaita-Ariño, and Eugenio Coronado
Phys. Rev. B 84, 184426 (2011)

Schematic image of the Fe8 SMM: combined action of a longitudinal dc magnetic field (applied along the easy axis of the magnetization) and a pulse of the field directed against the dc field.

Molecular Magnets on FM substrates

Coupling Single Molecule Magnets to Ferromagnetic Substrates.
A. Lodi Rizzini, C. Krull, T. Balashov, J. J. Kavich, A. Mugarza, P. S. Miedema, P. K. Thakur, V. Sessi, S. Klyatskaya, M. Ruben, S. Stepanow, and P. Gambardella
Phys. Rev. Lett. 107, 177205 (2011)

Element-resolved hysteresis loops of Ni (top) and Tb (bottom) for (a) TbPc2=Ni=Cuð100Þ,
(b) TbPc2=O=Ni=Cuð100Þ, (c) TbPc2=Li=Ni=Cuð100Þ, and (d) TbPc2=Ni=Agð100Þ measured at normal (left) and grazing
(right) incidence at T ¼ 8 K.

Order in 2D molecular magnets

Magnetic order in quasi-two-dimensional molecular magnets investigated with muon-spin relaxation.
A. J. Steele, T. Lancaster, S. J. Blundell, P. J. Baker, F. L. Pratt, C. Baines, M. M. Conner, H. I. Southerland, J. L. Manson, and J. A. SchlueterPhys. Rev. B 84, 064412 (2011)

The structure of [Cu(HF2)(pyz)2]PF6, as an example of the [M(HF2)(pyz)2]X series.

Decoherence in molecular manets

Decoherence in crystals of quantum molecular magnets.
S. Takahashi, I. S. Tupitsyn, J. van Tol, C. C. Beedle, D. N. Hendrickson & P. C. E. Stamp
Nature 476, 76 (2011)

Calculated contributions to the decoherence coming from the
coupling to nuclear spins, phonons and magnons. a, The three individual
contributions which sum to give the dimensionless decoherence rate cw5B/
T2Do, as a function of the qubit splitting in the case H\E^x.

Relaxation by MQT of a single molecular magnet

The Use of Magnetic Dilution To Elucidate the Slow Magnetic Relaxation Effects of a Dy2 Single-Molecule Magnet.
Fatemah Habib, Po-Heng Lin, Jerome Long, Ilia Korobkov, Wolfgang Wernsdorfer, and
Muralee Murugesu
JACS 133, 8830 (2011)

Assymetric Berry phase in molecular magnets

Asymmetric Berry-Phase Interference Patterns in a Single-Molecule Magnet.
H. M. Quddusi, J. Liu, S. Singh, K. J. Heroux, E. del Barco, S. Hill, and D. N. Hendrickson
Phys. Rev. Lett. 106, 227201 (2011)

Modulation of the QTM probabilities for resonances k = 0 (a) and k = 1 (b) as a function of HT applied at
different angles, within the hard plane of the Mn4-Bet SMM.

MQT of spin chirality in molecular clusters

Macroscopic quantum dynamics of toroidal moment in Ising-type rare-earth clusters.
D. I. Plokhov, A. K. Zvezdin, A. I. Popov
Phys. Rev. B 83, 184415 (2011)

Rabi-type oscillations between states.