papers

Publications (50)

cond-mat.supr-con2018

Coexistence of ferromagnetic and stripe-type antiferromagnetic spin fluctuations in YFeGe

Hongliang Wo, Qisi Wang, Yao Shen +18

We report neutron scattering measurements of single-crystalline YFeGe in the normal state, which has the same crystal structure to the 122 family of iron pnictide supercond…

cond-mat.str-el2003

Strongly Enhanced Magnetic Fluctuations in a Heavy-mass Layered Ruthenate

O. Friedt, P. Steffens, M. Braden +3

We have studied the magnetic excitations in CaSrRuO, x=0.52 and 0.62, which exhibit an anomalous high susceptibility and heavy mass Fermi liquid behavior. Our inela…

cond-mat.str-el2007

Field-induced paramagnons at the metamagnetic transition in Ca1.8Sr0.2RuO4

P. Steffens, Y. Sidis, P. Link +4

The magnetic excitations in Ca1.8Sr0.2RuO4 were studied across the metamagnetic transition and as a function of temperature using inelastic neutron scattering. At low temperature a…

cond-mat.str-el2016

Strong magnetoelastic coupling at the transition from harmonic to anharmonic order in NaFe(WO) with 3d configuration

S. Holbein, M. Ackermann, L. Chapon +9

The crystal structure of the double tungstate NaFe(WO) arises from that of the spin-driven multiferroic MnWO by inserting non-magnetic Na layers. NaFe(WO) exhib…

cond-mat.str-el2022

Disorder-induced broadening of the spin waves in a triangular-lattice quantum-spin-liquid candidate YbZnGaO

Zhen Ma, Zhao-Yang Dong, Jinghui Wang +15

Disorder is important in the study of quantum spin liquids, but its role on the spin dynamics remains elusive. Here, we explore the disorder effect by investigating the magnetic-fi…

cond-mat.str-el2020

Evidence for a three-dimensional quantum spin liquid in PbCuTeO

S. Chillal, Y. Iqbal, H. O. Jeschke +9

The quantum spin liquid (QSL) is a highly entangled magnetic state characterized by the absence of static magnetism in its ground state. Instead, the spins fluctuate in a highly co…

cond-mat.supr-con2014

Incommensurate antiferromagnetic fluctuations in single-crystalline LiFeAs studied by inelastic neutron scattering

N. Qureshi, P. Steffens, D. Lamago +7

We present an inelastic neutron scattering study on single-crystalline LiFeAs devoted to the characterization of the incommensurate antiferromagnetic fluctuations at $\mathbf{Q}=(0…

cond-mat.mes-hall2020

Spin-waves in the collinear antiferromagnetic phase of Mn$_\bf{5}$Si$_\bf{3}$

F. J. dos Santos, N. Biniskos, S. Raymond +7

By combining two independent approaches, inelastic neutron scattering measurements and density functional theory calculations, we study the spin-waves in the high-temperature colli…

cond-mat.str-el2010

Magnetic excitations in the metallic single-layer Ruthenates Ca(2-x)Sr(x)RuO(4) studied by inelastic neutron scattering

P. Steffens, O. Friedt, Y. Sidis +5

By inelastic neutron scattering, we have analyzed the magnetic correlations in the paramagnetic metallic region of the series Ca(2-x)Sr(x)RuO(4), 0.2<=x<=0.62. We find different co…

cond-mat.supr-con2018

Spin fluctuations in Sr2RuO4 from polarized neutron scattering: implications for superconductivity

P. Steffens, Y. Sidis, J. Kulda +4

Triplet pairing in Sr2RuO4 was initially suggested based on the hypothesis of strong ferromagnetic spin fluctuations. Using polarized inelastic neutron scattering, we accurately de…

cond-mat.str-el2017

Magnon dispersion in Ca2RuO4: impact of spin-orbit coupling and oxygen moments

S. Kunkemöller, E. Komleva, S. V. Streltsov +6

The magnon dispersion of CaRuO has been studied by polarized and unpolarized neutron scattering experiments on crystals containing 0, 1 and 10 % of Ti. The entire dispersio…

cond-mat.str-el2011

Hourglass dispersion in overdoped single-layered manganites

H. Ulbrich, P. Steffens, D. Lamago +2

The excitation spectrum in single-layered Nd(0.33)Sr(1.67)MnO4 and Pr(0.33)Ca(1.67)MnO4 resembles the hourglass-like excitation dispersion seen in various cuprates superconductors.…

cond-mat.mtrl-sci2023

An overview of the spin dynamics of antiferromagnetic MnSi

N. Biniskos, F. J. dos Santos, M. dos Santos Dias +8

The metallic compound MnSi hosts a series of antiferromagnetic phases which can be controlled by external stimuli such as temperature and magnetic field. In this work, we i…

cond-mat.supr-con2014

Anisotropy of incommensurate magnetic excitations in slightly overdoped BaKFeAs probed by polarized inelastic neutron scattering experiments

N. Qureshi, C. H. Lee, K. Kihou +3

Polarized neutron scattering experiments on the slightly overdoped superconductor BaKFeAs reveal broad magnetic resonance scattering peaking at approximatel…

cond-mat.supr-con2016

Suppression of low-energy longitudinal spin-excitations in Co-underdoped BaFe2As2

F. Waßer, C. H. Lee, K. Kihou +4

Polarized inelastic neutron scattering experiments were performed to study magnetic excitations in the normal and superconducting phases of Co-underdoped BaFeAs, which exhi…

cond-mat.str-el2023

Magnon dispersion in ferromagnetic SrRuO

K. Jenni, S. Kunkemöller, A. Tewari +6

The magnetic excitations in ferromagnetic SrRuO were studied by inelastic neutron scattering combining experiments on triple-axis and time-of-flight spectrometers with and with…

cond-mat.str-el2006

Magnetoelastic coupling across the metamagnetic transition in CaSrRuO (0.2 < x < 0.5)

J. Baier, P. Steffens, O. Schumann +11

The magnetoelastic coupling in CaSrRuO and in CaSrRuO has been studied combining high-resolution dilatometer and diffraction techniques. Bot…

cond-mat.supr-con2020

Multiple scattering camouflaged as magnetic stripes in single crystals of superconducting (La,Sr)CuO

A. -E. Ţuţueanu, T. B. Tejsner, M. E. Lǎcǎtuşu +6

Neutron diffraction has been a very prominent tool to investigate high-temperature superconductors, in particular through the discovery of an incommensurate magnetic signal known a…

cond-mat.str-el2021

Low-dimensional antiferromagnetic fluctuations in the heavy-fermion paramagnetic ladder UTe

W. Knafo, G. Knebel, P. Steffens +7

Inelastic-neutron-scattering measurements were performed on a single crystal of the heavy-fermion paramagnet UTe above its superconducting temperature. We confirm the presence…

cond-mat.mtrl-sci2018

Spin-fluctuations drive the inverse magnetocaloric effect in Mn5Si3

N. Biniskos, K. Schmalzl, S. Raymond +4

Inelastic neutron scattering measurements were performed on single crystals of the antiferromagnetic compound Mn5Si3 in order to investigate the relation between the spin dynamics…

cond-mat.supr-con2013

Universality of dispersive spin-resonance mode in superconducting BaFe2As2

C. H. Lee, P. Steffens, N. Qureshi +5

Spin fluctuations in superconducting BaFe2(As1-xPx)2 (x=0.34, Tc = 29.5 K) are studied using inelastic neutron scattering. Well-defined commensurate magnetic signals are observed a…

cond-mat.str-el2005

Thermodynamic Properties of (Ca,Sr)RuO in Magnetic Fields

J. Baier, T. Zabel, M. Kriener +9

We have studied the influence of a magnetic field on the thermodynamic properties of CaSrRuO in the intermediate metallic region with tilt and rotational distorti…

cond-mat.str-el2022

Inhomogeneous spin excitations in weakly coupled spin-1/2 chains

L. Shen, E. Campillo, O. Zaharko +8

We present a systematic inelastic neutron scattering and neutron diffraction study of the magnetic structure of the quasi-1D spin-1/2 magnet SrCo2V2O8, where the interchain couplin…

cond-mat.supr-con2011

Electron-Spin Excitation Coupling in an Electron Doped Copper Oxide Superconductor

Jun Zhao, F. C. Niestemski, Shankar Kunwar +8

High-temperature (high-Tc) superconductivity in the copper oxides arises from electron or hole doping of their antiferromagnetic (AF) insulating parent compounds. The evolution of…

cond-mat.str-el2015

Highly anisotropic magnon dispersion in Ca2RuO4: evidence for strong spin orbit coupling

S. Kunkemöller, D. Khomskii, P. Steffens +3

The magnon disp ersion in Ca2RuO4 has been determined by inelastic neutron scattering on single crytals containing 1% of Ti. The dispersion is well described by a conventional Heis…

cond-mat.supr-con2011

Incommensurate magnetic excitations in superconducting LiFeAs

N. Qureshi, P. Steffens, Y. Drees +8

Magnetic correlations in superconducting LiFeAs were studied by elastic and by inelastic neutron scattering experiments. There is no indication for static magnetic ordering but ine…

cond-mat.supr-con2012

Local magnetic anisotropy in BaFeAs: a polarized inelastic neutron scattering study

N. Qureshi, P. Steffens, S. Wurmehl +3

The anisotropy of the magnetic excitations in BaFeAs was studied by polarized inelastic neutron scattering which allows one to separate the components of the magnetic respo…

cond-mat.supr-con2015

Strong Interplay between Stripe Spin Fluctuations, Nematicity and Superconductivity in FeSe

Qisi Wang, Yao Shen, Bingying Pan +13

Elucidating the microscopic origin of nematic order in iron-based superconducting materials is important because the interactions that drive nematic order may also mediate the Coop…

cond-mat.str-el2005

High pressure diffraction studies on Ca2RuO4

P. Steffens, O. Friedt, P. Alireza +8

We studied the crystal and magnetic structure of Ca2RuO4 by different diffraction techniques under high pressure. The observed first order phase transition at moderate pressure (0.…

cond-mat.str-el2026

Vortex Crystal Candidate in the Triangular Quantum Antiferromagnet

J. Nagl, K. Yu. Povarov, B. Duncan +16

The prospect of merging the paradigms of geometric frustration on a triangular lattice and bond anisotropies in the strong spin-orbit coupling limit holds tremendous promise in the…

cond-mat.supr-con2019

Strong Spin Resonance Mode associated with suppression of soft magnetic ordering in Hole-doped Ba1-xNaxFe2As2

F. Wasser, J. -T. Park, S. Aswartham +6

Spin-resonance modes (SRM) are taken as evidence for magnetically driven pairing in Fe-based superconductors, but their character remains poorly understood. The broadness, the spli…

cond-mat.str-el2018

Pseudospin-lattice coupling in the spin-orbit Mott insulator Sr2IrO4

J. Porras, J. Bertinshaw, H. Liu +15

Spin-orbit entangled magnetic dipoles, often referred to as pseudospins, provide a new avenue to explore novel magnetism inconceivable in the weak spin-orbit coupling limit, but th…

cond-mat.str-el2024

Spin waves and three-dimensionality in the high-pressure antiferromagnetic phase of SrCu(BO)

E. Fogh, G. Giriat, M. E. Zayed +11

Quantum magnetic materials can provide explicit realizations of paradigm models in quantum many-body physics. In this context, SrCu(BO) is a faithful realization of the…

cond-mat.supr-con2024

Field-induced electronic phase separation in the high-temperature superconductor LaSrCuO

S. Holm-Dahlin, J. Larsen, H. Jacobsen +14

We present a combined neutron diffraction and high field muon spin rotation (SR) study of the magnetically ordered and superconducting phases of the high-temperature supercondu…

cond-mat.supr-con2017

Absence of a large superconductivity-induced gap in magnetic fluctuations of Sr2RuO4

S. Kunkemöller, P. Steffens, P. Link +3

Inelastic neutron scattering experiments on Sr2RuO4 determine the spectral weight of the nesting induced magnetic fluctuations across the superconducting transition. There is no ob…

cond-mat.str-el2022

Cascade of magnetic-field-driven quantum phase transitions in Ce3Pd20Si6

F. Mazza, P. Y. Portnichenko, S. Avdoshenko +8

Magnetically hidden order is a hypernym for electronic ordering phenomena that are visible to macroscopic thermodynamic probes but whose microscopic symmetry cannot be revealed wit…

cond-mat.supr-con2021

Neutron scattering studies on spin fluctuations in SrRuO

K. Jenni, S. Kunkemöller, P. Steffens +5

The magnetic excitations in SrRuO are studied by polarized and unpolarized neutron scattering experiments as a function of temperature. At the scattering vector of the Ferm…

cond-mat.str-el2020

Effect of Nd and Rh substitution on the spin dynamics of Kondo insulator CeFe2Al10

P. A. Alekseev, J. -M. Mignot, D. T. Adroja +7

The dynamic magnetic properties of the Kondo-insulator state in CeFe2Al10 (spin gap, resonance mode) have been investigated using polarized neutrons on a single crystal of pure CeF…

cond-mat.str-el2003

Anisotropy of the incommensurate fluctuations in Sr2RuO4: a study with polarized neutrons

M. Braden, P. Steffens, Y. Sidis +4

The anisotropy of the magnetic incommensurate fluctuations in Sr2RuO4 has been studied by inelastic neutron scattering with polarized neutrons. We find a sizeable enhancement of th…

cond-mat.str-el2017

Spin Resonance and Magnetic Order in an Unconventional Superconductor

D. G. Mazzone, S. Raymond, J. L. Gavilano +4

Unconventional superconductivity in many materials is believed to be mediated by magnetic fluctuations. It is an open question how magnetic order can emerge from a superconducting…

cond-mat.str-el2022

Topological magnon band structure of emergent Landau levels in a skyrmion lattice

T. Weber, D. M. Fobes, J. Waizner +16

The motion of a spin excitation across topologically non-trivial magnetic order exhibits a deflection that is analogous to the effect of the Lorentz force on an electrically charge…

cond-mat.str-el2021

Weak three-dimensional coupling of Heisenberg quantum spin chains in SrCuTeO

S. Chillal, A. T. M. N. Islam, P. Steffens +2

The magnetic Hamiltonian of the Heisenberg quantum antiferromagnet SrCuTeO is studied by inelastic neutron scattering technique on powder and single crystalline samples…

cond-mat.str-el2004

Structural aspects of metamagnetism in Ca_{2-x}Sr_{x}RuO_4 (0.2 < x < 0.5): field tuning of orbital occupation

M. Kriener, P. Steffens, J. Baier +12

The crystal structure of Ca_{2-x}Sr_xRuO_4 with 0.2 < x < 1.0 has been studied by diffraction techniques and by high resolution capacitance dilatometry as a function of temperature…

cond-mat.supr-con2016

Commensurate antiferromagnetic excitations as a signature of the pseudogap in the tetragonal high-Tc cuprate HgBaCuO

M. K. Chan, C. J. Dorow, L. Mangin-Thro +12

Antiferromagnetic correlations have been argued to be the cause of the d-wave superconductivity and the pseudogap phenomena exhibited by the cuprates. Although the antiferromagneti…

cond-mat.str-el2010

Evidence for charge orbital and spin stripe order in an overdoped manganite

H. Ulbrich, D. Senff, P. Steffens +5

We present diffraction data on a single-layered manganite La(0.42)Sr(1.58)MnO4 with hole doping (x>0.5). Overdoped La(0.42)Sr(1.58)MnO4 exhibits a complex ordering of charges, orbi…

cond-mat.str-el2017

Evidence for a spinon Fermi surface in a triangular lattice quantum spin liquid candidate

Yao Shen, Yao-Dong Li, Hongliang Wo +16

A quantum spin liquid is an exotic quantum state of matter in which spins are highly entangled and remain disordered down to zero temperature. Such a state of matter is potentially…

cond-mat.str-el2021

Spin dynamics of the quantum dipolar magnet YbGaO in an external field

E. Lhotel, L. Mangin-Thro, E. Ressouche +7

We investigate ytterbium gallium garnet YbGaO in the paramagnetic phase above the supposed magnetic transition at mK. Our study combines suscep…

cond-mat.str-el2023

Spin-wave dispersion and magnon chirality in multiferroic TbMnO3

S. Holbein, P. Steffens, S. Biesenkamp +4

Inelastic neutron scattering experiments combining time-of-flight and polarized techniques yield a comprehensive picture of the magnon dispersion in multiferroic TbMnO3 including t…

cond-mat.str-el2019

Fractionalized excitations in the partially magnetized spin liquid candidate YbMgGaO4

Yao Shen, Yao-Dong Li, H. C. Walker +7

Quantum spin liquids (QSLs) are exotic states of matter characterized by emergent gauge structures and fractionalized elementary excitations. The recently discovered triangular lat…

cond-mat.supr-con2012

Two Ising-like magnetic excitations in a single-layer cuprate superconductor

Yuan Li, G. Yu, M. K. Chan +10

There exists increasing evidence that the phase diagram of the high-transition temperature (Tc) cuprate superconductors is controlled by a quantum critical point. One distinct theo…