MPBH

The integrated network Mott Physics Beyond the Heisenberg Model (MPBH) united researchers across Switzerland in a collective effort to explore new aspects of Mott physics, in particular how spin-orbit interactions, in concert with strong electron correlations, lead to new and exotic quantum materials and phenomena.

The far-reaching achievements of the network were made possible only by assembling researchers with expertise in many complementary disciplines, who were hosted by the Swiss Federal Institute of Technology Lausanne (EPFL), the Paul Scherrer Institute (PSI), the University of Geneva (UNIGE), the Swiss Federal Institute of Technology Zurich (ETHZ) and the University of Zurich (UniZH).

The holistic approach of MPBH enabled us to synthesise and study promising materials by multiple techniques, thereby enabling profound advances in understanding their nature and quantum behaviour.

 

Publications

Persistent antiferromagnetic order in heavily overdoped Ca1-xLaxFeAs2

E. Martino; M. D. Bachmann; L. Rossi; K. A. Modic; I. Zivkovic et al. 

Journal Of Physics-Condensed Matter. 2019-12-04. Vol. 31, num. 48, p. 485705. DOI : 10.1088/1361-648X/ab3b43.

Magnetic and structural properties of Ni-substituted magnetoelectric Co4Nb2O9

H. Papi; V. Y. Favre; H. Ahmadvand; M. Alaei; M. Khondabi et al. 

Physical Review B. 2019-10-07. Vol. 100, num. 13, p. 134408. DOI : 10.1103/PhysRevB.100.134408.

Field-induced anisotropy in the quasi-two-dimensional weakly anisotropic antiferromagnet [CuCl(pyz)(2)]BF4

S. Kwon; M. Jeong; M. Kubus; B. Wehinger; K. W. Kraemer et al. 

Physical Review B. 2019-06-03. Vol. 99, num. 21, p. 214403. DOI : 10.1103/PhysRevB.99.214403.

Strain-engineering Mott-insulating La2CuO4

O. Ivashko; M. Horio; W. Wan; N. B. Christensen; D. E. McNally et al. 

Nature Communications. 2019-02-19. Vol. 10, p. 786. DOI : 10.1038/s41467-019-08664-6.

Probing multi-spinon excitations outside of the two-spinon continuum in the antiferromagnetic spin chain cuprate Sr2CuO3

J. Schlappa; U. Kumar; K. J. Zhou; S. Singh; M. Mourigal et al. 

Nature Communications. 2018-12-19. Vol. 9, p. 5394. DOI : 10.1038/s41467-018-07838-y.

Spin-Orbital Excitations in Ca2RuO4 Revealed by Resonant Inelastic X-Ray Scattering

L. Das; F. Forte; R. Fittipaldi; C. Fatuzzo; V. Granata et al. 

PHYSICAL REVIEW X. 2018. Vol. 8, num. 1. DOI : 10.1103/PhysRevX.8.011048.

Note: Commercial SQUID magnetometer-compatible NMR probe and its application for studying a quantum magnet

T. Vennemann; M. Jeong; D. Yoon; A. Magrez; H. Berger et al. 

REVIEW OF SCIENTIFIC INSTRUMENTS. 2018. Vol. 89, num. 4. DOI : 10.1063/1.5023675.

Dispersive magnetic and electronic excitations in iridate perovskites probed by oxygen K-edge resonant inelastic x-ray scattering

X. Lu; P. Olalde-Velasco; Y. Huang; V. Bisogni; J. Pelliciari et al. 

Physical Review B. 2018. Vol. 97, num. 4. DOI : 10.1103/PhysRevB.97.041102.

Direct electric field control of the skyrmion phase in a magnetoelectric insulator

A. Kruchkov; J. White; M. Bartkowiak; I. Zivkovic; A. Magrez et al. 

Scientific Reports. 2018. Vol. 8. DOI : 10.1038/s41598-018-27882-4.

A-cation control of magnetoelectric quadrupole order in A(TiO)Cu-4(PO4)(4) (A = Ba, Sr, and Pb)

K. Kimura; M. Toyoda; P. Babkevich; K. Yamauchi; M. Sera et al. 

Physical Review B. 2018. Vol. 97, num. 13. DOI : 10.1103/PhysRevB.97.134418.

Charge-Stripe Order and Superconductivity in Ir1−xPtxTe2

O. Ivashko; L. Yang; E. Destraz; E. Martino; Y. Chen et al. 

Scientific Reports. 2017-12-07. Vol. 7, p. 17157. DOI : 10.1038/s41598-017-16945-7.

Mapping the lattice dynamical anomaly of the order parameters across the Verwey transition in magnetite

S. Borroni; G. S. Tucker; F. Pennacchio; J. Rajeswari; U. Stuhr et al. 

New Journal of Physics. 2017. Vol. 19, p. 103013. DOI : 10.1088/1367-2630/aa83a3.

Magnetic structure of Ba(TiO)Cu4(PO4)4 probed using spherical neutron polarimetry

P. Babkevich; L. Testa; K. Kimura; T. Kimura; G. S. Tucker et al. 

Physical Review B. 2017. Vol. 96, num. 21, p. 214436. DOI : 10.1103/PhysRevB.96.214436.

Electronic and magnetic excitations in the half-stuffed Cu-O planes of Ba2Cu3O4Cl2 measured by resonant inelastic x-ray scattering

S. Fatale; C. G. Fatuzzo; P. Babkevich; N. E. Shaik; J. Pelliciari et al. 

Physical Review B. 2017. Vol. 96, num. 11, p. 115149. DOI : 10.1103/PhysRevB.96.115149.

Hallmarks of Hunds coupling in the Mott insulator Ca2RuO4

D. Sutter; C. G. Fatuzzo; S. Moser; M. Kim; R. Fittipaldi et al. 

Nature Communications. 2017. Vol. 8, p. 15176. DOI : 10.1038/ncomms15176.

J1−J2 square-lattice Heisenberg antiferromagnets with 4d1 spins: AMoOPO4Cl (A=K,Rb)

H. Ishikawa; N. Nakamura; M. Yoshida; M. Takigawa; P. Babkevich et al. 

Physical Review B. 2017. Vol. 95, num. 6, p. 064408. DOI : 10.1103/PhysRevB.95.064408.

Magnetodielectric detection of magnetic quadrupole order in Ba(TiO)Cu4(PO4)4 with Cu4O12 square cupolas

K. Kimura; P. Babkevich; M. Sera; M. Toyoda; K. Yamauchi et al. 

Nature Communications. 2016-10-04. Vol. 7, p. 13039. DOI : 10.1038/ncomms13039.

MnO nanoparticles as the cause of ferromagnetism in bulk dilute Mn-doped ZnO

D. Lancon; G. J. Nilsen; A. R. Wildes; K. Nemkovski; P. Huang et al. 

Applied Physics Letters. 2016. Vol. 109, num. 25, p. 252405. DOI : 10.1063/1.4972956.

Probing strongly hybridized nuclear-electronic states in a model quantum ferromagnet

I. Kovacevic; P. Babkevich; M. Jeong; J. O. Piatek; G. Boero et al. 

Physical Review B. 2016. Vol. 94, num. 21, p. 214433. DOI : 10.1103/PhysRevB.94.214433.

Electromagnon dispersion probed by inelastic X-ray scattering in LiCrO2

S. Toth; B. Wehinger; K. Rolfs; T. Birol; U. Stuhr et al. 

Nature Communications. 2016. Vol. 7, p. 13547. DOI : 10.1038/ncomms13547.

Magnetic Excitations and Electronic Interactions in Sr2CuTeO6: A Spin-1/2 Square Lattice Heisenberg Antiferromagnet

P. Babkevich; V. M. Katukuri; B. Fak; S. Rols; T. Fennell et al. 

Physical Review Letters. 2016. Vol. 117, num. 23, p. 237203. DOI : 10.1103/PhysRevLett.117.237203.

Dimensional Reduction in Quantum Dipolar Antiferromagnets

P. Babkevich; M. Jeong; Y. Matsumoto; I. Kovacevic; A. Finco et al. 

Physical Review Letters. 2016. Vol. 116, num. 19, p. 197202. DOI : 10.1103/PhysRevLett.116.197202.

Pressure dependence of the structure and electronic properties of Sr3Ir2O7

C. Donnerer; Z. Feng; J. G. Vale; S. N. Andreev; I. V. Solovyev et al. 

Physical Review B. 2016. Vol. 93, num. 17, p. 174118. DOI : 10.1103/PhysRevB.93.174118.

One-dimensional Bose-Einstein condensation of photons in a microtube

A. J. Kruchkov 

Physical Review A. 2016. Vol. 93, num. 4, p. 043817. DOI : 10.1103/PhysRevA.93.043817.

Origin of the Spin-Orbital Liquid State in a Nearly J=0 Iridate Ba3ZnIr2O9

A. Nag; S. Middey; S. Bhowal; S. K. Panda; R. Mathieu et al. 

Physical Review Letters. 2016. Vol. 116, num. 9, p. 097205. DOI : 10.1103/PhysRevLett.116.097205.

Correlation of the superconducting critical temperature with spin and orbital excitations in (CaxLa1− x)(Ba1. 75− xLa 0. 25) Cu3Oy as measured by resonant inelastic x-ray scattering

D. S. Ellis; Y-B. Huang; P. Olalde-Velasco; M. Dantz; J. Pelliciari et al. 

Physical Review B. 2015. Vol. 92, num. 10, p. 104507. DOI : 10.1103/PhysRevB.92.104507.

One-dimensional quantum magnetism in the anhydrous alum KTi(SO4)(2)

G. J. Nilsen; A. Araja; A. A. Tsirlin; H. Mutka; D. Kasinathan et al. 

New Journal Of Physics. 2015. Vol. 17, p. 113035. DOI : 10.1088/1367-2630/17/11/113035.

Magnons in tetragonal CuO

S. Moser; N. E. Shaik; D. Samal; S. Fatale; B. Dalla Piazza et al. 

Physical Review B. 2015. Vol. 92, num. 14, p. 140404. DOI : 10.1103/PhysRevB.92.140404.

Sc2Ga2CuO7: A possible quantum spin liquid near the percolation threshold

R. Kumar; P. Khuntia; D. Sheptyakov; P. G. Freeman; H. M. Rønnow et al. 

Physical Review B Condensed Matter. 2015. Vol. 92, p. 180411(R). DOI : 10.1103/PhysRevB.92.180411.

Intrachain antiferromagnetic exchange in a 1D branched-chain built of two different copper(II) centres interlinked by end-on azido and phenoxo bridges: electron density map, electrochemical and magnetic properties

F. Fadaee; M. Amirnasr; K. Prsa; P. Pattison; N. E. Shaik et al. 

Rsc Advances. 2015. Vol. 5, num. 74, p. 59926-59934. DOI : 10.1039/c4ra13755h.

Evidence of quantum dimer excitations in Sr3Ir2O7

M. M. Sala; V. Schnells; S. Boseggia; L. Simonelli; A. Al-Zein et al. 

Physical Review B. 2015. Vol. 92, num. 2, p. 024405. DOI : 10.1103/PhysRevB.92.024405.

Importance of XY anisotropy in Sr2IrO4 revealed by magnetic critical scattering experiments

J. G. Vale; S. Boseggia; H. C. Walker; R. Springell; Z. Feng et al. 

Physical Review B. 2015. Vol. 92, num. 2, p. 020406. DOI : 10.1103/PhysRevB.92.020406.

Magnetic model in multiferroic NdFe3(BO3)(4) investigated by inelastic neutron scattering

S. Hayashida; M. Soda; S. Itoh; T. Yokoo; K. Ohgushi et al. 

Physical Review B. 2015. Vol. 92, num. 5, p. 054402. DOI : 10.1103/PhysRevB.92.054402.

Pressure dependence of the magnetic order in CrAs: A neutron diffraction investigation

L. Keller; J. S. White; M. Frontzek; P. Babkevich; M. A. Susner et al. 

Physical Review B. 2015. Vol. 91, num. 2. DOI : 10.1103/PhysRevB.91.020409.

Pressure induced evolution of superconductivity and magnetic hourglass dispersion in Fe1.02Te0.7Se0.3

D. Lancon; N. Tsyrulin; M. Boehm; R. Viennois; S. Zabihzadeh et al. 

New Journal Of Physics. 2015. Vol. 17. DOI : 10.1088/1367-2630/17/4/043020.

Spin-orbit-induced orbital excitations in Sr2RuO4 and Ca2RuO4: A resonant inelastic x-ray scattering study

C. G. Fatuzzo; M. Dantz; S. Fatale; P. Olalde-Velasco; N. E. Shaik et al. 

Physical Review B. 2015. Vol. 91, num. 15, p. 155104. DOI : 10.1103/PhysRevB.91.155104.

Crystal Structure, Transport, and Magnetic Properties of an Ir6+ Compound Ba8Al2IrO14

L. Yang; A. Pisoni; A. Magrez; S. Katrych; A. Arakcheeva et al. 

Inorganic Chemistry. 2015. Vol. 54, num. 9, p. 4371-4376. DOI : 10.1021/acs.inorgchem.5b00157.

Fractional excitations in the square-lattice quantum antiferromagnet

B. D. Piazza; M. Mourigal; N. B. Christensen; G. J. Nilsen; P. Tregenna-Piggott et al. 

Nature Physics. 2015. Vol. 11, num. 1, p. 62-68. DOI : 10.1038/Nphys3172.

Asymmetry of collective excitations in electron- and hole-doped cuprate superconductors

W. S. Lee; J. J. Lee; E. A. Nowadnick; S. Gerber; W. Tabis et al. 

Nature Physics. 2014. Vol. 10, num. 11, p. 883-889. DOI : 10.1038/nphys3117.

Self-doping processes between planes and chains in the metal-to-superconductor transition of YBa2Cu3O6.9

M. Magnuson; T. Schmitt; V. N. Strocov; J. Schlappa; A. S. Kalabukhov et al. 

Scientific Reports. 2014. Vol. 4, p. 7017. DOI : 10.1038/srep07017.

Itinerant effects and enhanced magnetic interactions in Bi-based multilayer cuprates

M. P. M. Dean; A. J. A. James; A. C. Walters; V. Bisogni; I. Jarrige et al. 

Physical Review B. 2014. Vol. 90, num. 22. DOI : 10.1103/PhysRevB.90.220506.

Femtosecond Dynamics of Momentum-Dependent Magnetic Excitations from Resonant Inelastic X-Ray Scattering in CaCu2O3

V. Bisogni; S. Kourtis; C. Monney; K. Zhou; R. Kraus et al. 

Physical Review Letters. 2014. Vol. 112, num. 14. DOI : 10.1103/PhysRevLett.112.147401.

Charge-orbital-lattice coupling effects in the dd excitation profile of one-dimensional cuprates

J. J. Lee; B. Moritz; W. S. Lee; M. Yi; C. J. Jia et al. 

Physical Review B. 2014. Vol. 89, num. 4. DOI : 10.1103/PhysRevB.89.041104.

Angle-Resolved Photoemission Spectroscopy of Tetragonal CuO: Evidence for Intralayer Coupling Between Cupratelike Sublattices

S. Moser; L. Moreschini; H. Yang; D. Innocenti; F. Fuchs et al. 

Physical Review Letters. 2014. Vol. 113, num. 18, p. 187001. DOI : 10.1103/PhysRevLett.113.187001.

Anisotropic softening of magnetic excitations along the nodal direction in superconducting cuprates

M. Guarise; B. Dalla Piazza; H. Berger; E. Giannini; T. Schmitt et al. 

Nature Communications. 2014. Vol. 5, p. 5760. DOI : 10.1038/ncomms6760.

Nonequilibrium hysteresis and spin relaxation in the mixed-anisotropy dipolar-coupled spin-glass LiHo0.5Er0.5F4

J. O. Piatek; I. Kovacevic; P. Babkevich; B. D. Piazza; S. Neithardt et al. 

Physical Review B. 2014. Vol. 90, num. 17. DOI : 10.1103/PhysRevB.90.174427.

Exploring the spin-orbital ground state of Ba3CuSb2O9

A. Smerald; F. Mila 

Physical Review B. 2014. Vol. 90, num. 9. DOI : 10.1103/PhysRevB.90.094422.

Correlated Decay of Triplet Excitations in the Shastry-Sutherland Compound SrCu2(BO3)(2)

M. E. Zayed; C. Rueegg; T. Straessle; U. Stuhr; B. Roessli et al. 

Physical Review Letters. 2014. Vol. 113, num. 6, p. 067201. DOI : 10.1103/PhysRevLett.113.067201.

Bilayer splitting and wave functions symmetry in Sr3Ir2O7

L. Moreschini; S. Moser; A. Ebrahimi; B. Dalla Piazza; K. S. Kim et al. 

Physical Review B. 2014. Vol. 89, num. 20, p. 201114(R). DOI : 10.1103/PhysRevB.89.201114.

Nodal Landau Fermi-liquid quasiparticles in overdoped La1.77Sr0.23CuO4

C. G. Fatuzzo; Y. Sassa; M. Månsson; S. Pailhès; O. J. Lipscombe et al. 

Physical Review B. 2014. Vol. 89, num. 20. DOI : 10.1103/PhysRevB.89.205104.

L4Fe2As2Te1-xO4-yFy (L = Pr, Sm, Gd): A layered oxypnictide superconductor with T-c up to 45 K

S. Katrych; A. Pisoni; S. Bosma; S. Weyeneth; N. D. Zhigadlo et al. 

Physical Review B. 2014. Vol. 89, num. 2. DOI : 10.1103/PhysRevB.89.024518.

Quantum and thermal ionic motion, oxygen isotope effect, and superexchange distribution in La2CuO4

P. S. Haefliger; S. Gerber; R. Pramod; V. I. Schnells; B. Dalla Piazza et al. 

Physical Review B. 2014. Vol. 89, num. 8, p. 085113. DOI : 10.1103/PhysRevB.89.085113.

Orbital occupancies and the putative j(eff)=1/2 ground state in Ba2IrO4: A combined oxygen K-edge XAS and RIXS study

M. M. Sala; M. Rossi; S. Boseggia; J. Akimitsu; N. B. Brookes et al. 

Physical Review B. 2014. Vol. 89, num. 12, p. 121101. DOI : 10.1103/PhysRevB.89.121101.

The electronic structure of the high-symmetry perovskite iridate Ba2IrO4

S. Moser; L. Moreschini; A. Ebrahimi; B. Dalla Piazza; M. Isobe et al. 

New Journal of Physics. 2014. Vol. 16, num. 1, p. 013008. DOI : 10.1088/1367-2630/16/1/013008.

Theory of spin excitations in a quantum spin-nematic state

A. Smerald; N. Shannon 

Physical Review B. 2013. Vol. 88, num. 18. DOI : 10.1103/PhysRevB.88.184430.

Robustness of Basal-Plane Antiferromagnetic Order and the Jeff=1/2 State in Single-Layer Iridate Spin-Orbit Mott Insulators

S. Boseggia; R. Springell; H. Walker; H. M. Rønnow; C. Rüegg et al. 

Physical Review Letters. 2013. Vol. 110, num. 11. DOI : 10.1103/PhysRevLett.110.117207.

Glassy low-energy spin fluctuations and anisotropy gap in La1.88Sr0.12CuO4

A. T. Romer; J. Chang; N. B. Christensen; B. M. Andersen; K. Lefmann et al. 

Physical Review B. 2013. Vol. 87, num. 14. DOI : 10.1103/PhysRevB.87.144513.

Huge critical current density and tailored superconducting anisotropy in SmFeAsO0.8F0.15 by low-density columnar-defect incorporation

L. Fang; Y. Jia; V. Mishra; C. Chaparro; V. K. Vlasko-Vlasov et al. 

Nature Communications. 2013. Vol. 4. DOI : 10.1038/ncomms3655.

Locking of iridium magnetic moments to the correlated rotation of oxygen octahedra in Sr2IrO4 revealed by x-ray resonant scattering

S. Boseggia; H. C. Walker; J. Vale; R. Springell; Z. Feng et al. 

Journal Of Physics-Condensed Matter. 2013. Vol. 25, num. 42, p. 191071. DOI : 10.1088/0953-8984/25/42/422202.

Phase diagram of the spin-1 Heisenberg model with three-site interactions on the square lattice

F. Michaud; F. Mila 

Physical Review B. 2013. Vol. 88, num. 9. DOI : 10.1103/PhysRevB.88.094435.

Possible spin-orbit driven spin-liquid ground state in the double perovskite phase of Ba3YIr2O9

T. Dey; A. V. Mahajan; R. Kumar; B. Koteswararao; F. C. Chou et al. 

Physical Review B Condensed Matter. 2013. Vol. 88, p. 134425. DOI : 10.1103/PhysRevB.88.134425.

Spin-gap evolution upon Ca doping in the spin-ladder series Sr(14−x)CaxCu24O41 studied by inelastic neutron scattering

G. Deng; N. Tsyrulin; P. Bourges; D. Lamago; H. M. Ronnow et al. 

Physical Review B. 2013. Vol. 88, num. 1. DOI : 10.1103/PhysRevB.88.014504.

Temperature-dependent electron-phonon coupling in La_{2−x}Sr_{x}CuO_{4} probed by femtosecond x-ray diffraction

B. Mansart; M. J. G. Cottet; G. F. Mancini; T. Jarlborg; S. B. Dugdale et al. 

Physical Review B. 2013. Vol. 88, num. 5, p. 054507. DOI : 10.1103/PhysRevB.88.054507.

Phase diagram with an enhanced spin-glass region of the mixed Ising–XY magnet LiHoxEr1-xF4

J. Piatek; B. Dalla Piazza; N. Nikseresht; N. Tsyrulin; I. Zivkovic et al. 

Physical Review B Condensed Matter. 2013. Vol. 88, p. 014408. DOI : 10.1103/PhysRevB.88.014408.

Low-temperature spin dynamics of a valence bond glass in Ba2YMoO6

M. de Vries; J. O. Piatek; M. Misek; J. S. Lord; H. M. Ronnow et al. 

New Journal of Physics. 2013. Vol. 15, p. 043024. DOI : 10.1088/1367-2630/15/4/043024.

Determining the Short-Range Spin Correlations in the Spin-Chain Li2CuO2 and CuGeO3 Compounds Using Resonant Inelastic X-Ray Scattering

C. Monney; V. Bisogni; K-J. Zhou; R. Kraus; V. N. Strocov et al. 

Physical Review Letters. 2013. Vol. 110, num. 8. DOI : 10.1103/PhysRevLett.110.087403.