I10-Beamline for Advanced Dichroism - scattering
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Duncan
Miertschin
,
Sundar
Kunwar
,
Balaram
Regmi
,
Poshan
Kandel
,
Sanjib
Thapa
,
Davis
Crater
,
Luca
Basso
,
Adam
Dodson
,
Zheng
Gai
,
Lide
Yao
,
Yu-Wei
Chen
,
Peter
Bencok
,
Armin
Kleibert
,
Yen-Lin
Huang
,
Andy
Mounce
,
Paul G.
Kotula
,
Sebastiaan
Van Dijken
,
Alessandro R.
Mazza
,
Thomas Z.
Ward
,
Nick
Shepelin
,
Alan
Farhan
Diamond Proposal Number(s):
[40992]
Open Access
Abstract: Multiferroics that combine ferroelectricity and magnetic order are attractive for electronic and spintronic technologies, yet chemical disorder that promotes relaxor ferroelectricity usually suppresses long-range magnetic order. Here, we report entropy-stabilized relaxor multiferroicity in epitaxial hexagonal (Tb0.2Dy0.2Ho0.2Lu0.2Yb0.2)FeO3 thin films. Structural, magnetic, dielectric, and synchrotron spectroscopic measurements show the coexistence of relaxor ferroelectricity and long-range ferromagnetic order. We find that improper ferroelectricity remains robust against A-site configurational disorder, while the Fe sublattice preserves magnetic exchange. This separation of the microscopic origins of the polar and magnetic responses enables chemically disordered multiferroicity. Our results establish entropy engineering in hexagonal ferrites as a route toward multifunctional oxide thin films and provide a general design strategy for high-entropy multiferroics.
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Sep 2026
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I10-Beamline for Advanced Dichroism - scattering
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Diamond Proposal Number(s):
[38952]
Open Access
Abstract: High-entropy perovskite oxides offer a promising platform for tailoring magnetic functionality through compositional complexity; however, it remains unclear how targeted substitution of 4d transition metals modifies oxygen-mediated electronic structure and element-specific magnetic interactions. To address this question, we investigate the effect of Mo and Ru substitution on the electronic structure and magnetism of high-entropy perovskite oxide thin films using O K-edge and transition-metal L-edge X-ray absorption spectroscopy, X-ray magnetic circular dichroism (XMCD), and X-ray linear dichroism. O K-edge spectra reveal that Ru enhances O 2p–metal d hybridization, whereas Mo modifies charge distribution and local exchange pathways within the transition-metal sublattice. Multiplet analysis shows that Mn and Ni retain stable Mn4+ and Ni2+ states, while Co acts as the primary charge-compensation reservoir through changes in the Co2+/Co3+ ratio. Temperature-dependent XMCD demonstrates that these substitutions selectively reshape the magnetic exchange network, redistributing spin polarization among the constituent elements. Quantitative XMCD sum-rule analysis reveals that Mo substitution produces the highest reconstructed total magnetic moment across the measured temperature range, reaching values at low temperature that are nearly an order of magnitude larger than those observed in the Ru-containing compositions. These results establish a composition-driven strategy for tuning covalency, charge redistribution, and the balance between localized and itinerant magnetism in high-entropy oxide thin films, providing a pathway toward the design of tunable spintronic and multifunctional oxide materials.
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Aug 2026
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I10-Beamline for Advanced Dichroism - scattering
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Abstract: We report new developments on the I10 (BLADE) beamline of Diamond Light Source. The beamline exploits dichroism in X-ray scattering and absorption to investigate magnetic ordering and electronic structure of magnetic materials. Operating in soft X-ray region, it covers L-edges of the 3d transition metals and the M-edge of 4f rare earth elements. In this paper, we present an overview of the beamline, describe its two endstations along with recent upgrades.
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Jul 2026
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I10-Beamline for Advanced Dichroism - scattering
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Duncan
Miertschin
,
Alessandro R.
Mazza
,
Balaram
Regmi
,
Sundar
Kunwar
,
Poshan
Kandel
,
Ryan
Mueller
,
Clayton
Hearn
,
Peter
Bencok
,
David A.
Jack
,
Thomas
Prokscha
,
Andreas
Suter
,
Zaher
Salman
,
Alan
Farhan
,
Thomas Zac
Ward
Diamond Proposal Number(s):
[38952]
Open Access
Abstract: Chemical disorder in compositionally complex perovskite oxides generates a broad distribution of exchange pathways and spin states, but the microscopic origin and spatial homogeneity of the resulting magnetic phases remain debated. Here, we tune the Mn fraction (x = 0.2–0.6) in epitaxial La(Cr, Mn, Fe, Co, Ni)O3 thin films and resolve the coupled evolution of valence, spin state, and magnetism using element-specific x-ray absorption spectroscopy and x-ray magnetic circular dichroism (XMCD). Mn enrichment drives an internal redistribution of charge, in which Mn evolves toward a Mn3+-rich mixed valence, while Co converts from predominantly Co3+ to high-spin Co2+. This valence/spin-state coupling amplifies the Mn- and Co-derived ferromagnetic response by nearly an order of magnitude while increasing the magnetic onset temperature to at least 250 K, whereas Fe and Cr remain essentially trivalent with weak dichroism. Depth-resolved low-energy muon spin spectroscopy (LE-μSR) shows magnetic homogeneity through the film thickness, with a secondary relaxation maximum near 25 K indicating a low-temperature dynamical crossover consistent with frustrated magnetism in a strongly disordered spin lattice.
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May 2026
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I10-Beamline for Advanced Dichroism - scattering
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Roxana
Capu
,
Ryan
Thompson
,
C. Willem
Rischau
,
Marli R.
Cantarino
,
Premysl
Marsik
,
Sergey L.
Bud'Ko
,
Neven
Biškup
,
María
Varela
,
Yurii G.
Pashkevich
,
Serhii M.
Orel
,
Thomas
Prokscha
,
Andreas
Suter
,
Jiangtao
Zhao
,
Ugwumsinachi
Oji
,
Marco
Bonura
,
Peter
Bencok
,
Zaher
Salman
,
Stefano
Gariglio
,
Christian
Bernhard
,
Subhrangsu
Sarkar
Diamond Proposal Number(s):
[38112]
Open Access
Abstract: We report the dielectric and magnetic properties of epitaxial thin films of the high entropy oxide (HEO) perovskite Nd(Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)O3, which orders magnetically below Tmag≈190 K. At T ≫ Tmag, the dielectric response reveals a Debye-type frequency dependence with a zero-frequency dielectric constant of
≈230–250. The dc bias voltage loops of
are reversible but exhibit three distinct peaks centred at zero and finite positive and negative voltage. We provide evidence that the zero-bias peak is governed by the oxygen sublattice while the finite bias peaks originate from cationic dipoles. The maximal response of the latter appears to be shifted to finite bias by a static uncompensated electric field due to a vertical gradient of the oxygen content. Below Tmag, this anomalous dielectric response is strongly suppressed, presumably by magnetostriction that counteracts and freezes the ionic displacements. These findings indicate a unique correlation between configurational entropy, dielectric response, and magnetic properties. In combination with a large dielectric strength, it enables a non-hysteretic tuning of the dielectric response of magnetoelectronic devices with multiple parameters like temperature, electric, and magnetic field. This HEO is equally interesting for fundamental studies of competing electric and magnetic orders in strongly disordered materials.
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Apr 2026
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I10-Beamline for Advanced Dichroism - scattering
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Margaret A.
Anderson
,
Megan E.
Goh
,
Yang
Zhang
,
Kyeong-Yoon
Baek
,
Michael
Schulze
,
Mario
Brützam
,
Christoph
Liebald
,
Chris
Lygouras
,
Dan Ferenc
Segedin
,
Aaron M.
Day
,
Zubia
Hasan
,
Donald A.
Walko
,
Hua
Zhou
,
Peter
Bencok
,
Alpha T.
N'Diaye
,
Charles M.
Brooks
,
Ismail
El Baggari
,
John T.
Heron
,
S. M.
Koohpayeh
,
Daniel
Rytz
,
Christo
Guguschev
,
Julia A.
Mundy
Diamond Proposal Number(s):
[41817]
Abstract: he pyrochlore vanadates are compelling candidates for next-generation dissipationless devices.
and
are ferromagnetic insulators (T
70 K) that are believed to exhibit the magnon Hall effect and are expected to host topological magnons. Their completely dissipationless magnon edge states could be harnessed to realize low-power information transport in spintronic or magnonic devices. As a crucial step in the realization of devices, we synthesize the first thin films of pyrochlore
on isostructural
substrates and explore the evolution of their magnetic properties down to the ultrathin limit. All films are insulating ferromagnets with transition temperatures of up to the bulk value (T
68 K) that decrease with thickness according to finite-size effects. Our films also exhibit a change in anisotropy from in-plane to out-of-plane easy axis coincident with the development of partial strain relaxation and nonzero magnetic hysteresis in an applied field. This evolution demonstrates the impact of strain on magnetic anisotropy and paves the way to tunable magnon topology.
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Mar 2026
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I10-Beamline for Advanced Dichroism - scattering
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Diamond Proposal Number(s):
[36197]
Abstract: Heterostructures composed of heavy metal and van der Waals (vdW) magnets serve as platforms to investigate magnetotransport properties, enabling the electric readout of the spin-flop transition in the vdW antiferromagnet. We investigate the spin and orbital contributions to magnetism in Pt/exfoliated multilayer CrPS4 heterostructure using the synchrotron-radiation based x-ray magnetic circular dichroism technique measured in the total electron yield (TEY) mode. The TEY detection, with probing depth of 5–10 nm, mainly reflects the interfacial magnetic behavior near the Pt/CrPS4 boundary. A spin-flop transition appears near 0.7 T in both the CrPS4 single crystal and the Pt/CrPS4 heterostructures. The total Cr moment remains ∼2 μB/f.u. in both systems at 14 T and 6 K. In Pt/CrPS4, the orbital moment is strongly modulated by Pt, as manifested in the enhancement from ∼0.1 μB/f.u. in CrPS4 to ∼0.5 μB/f.u. in Pt/CrPS4, an effect attributable to the strong spin–orbit coupling with Pt. At 25 K, the total Cr moment reduces to ∼1.1 μB/f.u. in both systems. The Cr orbital moment in CrPS4 remains low ∼0.1 μB/f.u., whereas in Pt/CrPS4 it remains high ∼0.5 μB/f.u. These findings provide qualitative evidence of robust spin–orbit coupling and orbital hybridization at Pt/CrPS4 interface, and highlight the potential of heavy metal/vdW antiferromagnet heterostructures for spin-orbitronic device applications.
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Feb 2026
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I10-Beamline for Advanced Dichroism - scattering
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Jiahao
Liu
,
Xingtai
Chen
,
Jiaqi
Lu
,
Weixiang
Li
,
Zhaochun
Liu
,
Yongzhuo
Zhang
,
Peter
Bencok
,
Paul
Steadman
,
Wenqing
Liu
,
Weisheng
Zhao
,
Shouzhong
Peng
Diamond Proposal Number(s):
[36197]
Open Access
Abstract: Exchange bias fields at antiferromagnet/ferromagnet (AFM/FM) interfaces play a crucial role in the performance of spintronic devices. Despite extensive research, the physical origin of exchange bias remains incompletely understood. In this study, we conduct a detailed investigation of a prototype AFM/FM interface widely used in spintronic applications, i.e., the IrMn/CoFeB interface. High-resolution synchrotron X-ray measurements reveal the existence of uncompensated Mn spins at the interface. While most of these spins are strongly coupled to the adjacent CoFeB layer, a small fraction remains pinned to the underlying IrMn underlayer. Element-specific X-ray magnetic circular dichroism hysteresis loops show that these pinned spins can be switched by increasing the annealing magnetic field. Furthermore, micromagnetic simulations indicate that an imbalance in the quantity of antiparallel pinned spins contributes to the observed variation in exchange bias. Overall, these findings offer important insights into the microscopic mechanisms governing exchange bias and its tunability.
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Jan 2026
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I10-Beamline for Advanced Dichroism - scattering
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Yuan
Huang
,
Grigore A.
Timco
,
George F. S.
Whitehead
,
Selena J.
Lockyer
,
Niklas
Geue
,
Zhibo
Qi
,
Adam
Brookfield
,
Peter
Bencok
,
Perdita E.
Barran
,
Nicholas F.
Chilton
,
Michael L.
Baker
,
Eric J. L.
Mcinnes
,
Richard E. P.
Winpenny
Diamond Proposal Number(s):
[34857, 35250]
Open Access
Abstract: A rare example of a seven-membered heterometallic ring [CrIII6CeIIIF7(O2CtBu)14(THF)2] (MeCN)2 (1) and five eight-membered heterometallic rings, [nPr2NH2][CrIII6LnIII2F8(O2CtBu)17Lx] (2, Ln = Ce, L = HO2CtBu, x = 2, 3, Ln = Y, L = H2O, x = 1, 4, Ln = Gd, L = HO2CtBu, x = 1; 5, Ln = Tb, L = HO2CtBu, x = 1; 6, Ln = Yb, no L) have been synthesized and structurally characterized through X-ray diffraction. The structures consist of eight metals in an octagon, with Cr…Cr and Cr…Ln edges bridged by a fluoride and two carboxylates, while the Ln…Ln edges are bridged by a fluoride and three carboxylates. The magnetisation and susceptibility of these compounds were measured using SQUID magnetometry and electron paramagnetic resonance (EPR) spectroscopy. The magnetic data were fitted with antiferromagnetic exchange interactions between chromium(III) ions, which can be fitted in the {Cr6Y2} complex 3 and these parameters were then used to fit the magnetic properties of the {Cr6Gd2} complex 4 adding in exchange interactions between the CrIII and GdIII The magnetisation and susceptibility below 80 K of 1 and 2 were fitted on the basis of CASSCF-SO calculations at the CeIII site, and showed a weak ferromagnetic interaction between CrIII and CeIII. For 5 and 6 the magnetisation data was fitted by subtracting the data for 3 and treating the residual data as a {Tb2} and {Yb2} dimer respectively. The EPR spectra are rich, and for 3 can be modelled as due to S = 1 and S = 2 states of the {Cr6} chain. The spectra of 1 and 2 are similar, consistent with very weak interactions between the CeIII and the {Cr6} chain, while the spectra of 5 and 6 are different to that of 3, suggesting that the low temperature spectroscopy is due to a spin system in which the LnIII ions interact with the {Cr6} chain.
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Dec 2025
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I10-Beamline for Advanced Dichroism - scattering
I21-Resonant Inelastic X-ray Scattering (RIXS)
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Andrey D.
Poletayev
,
Robert J.
Green
,
Jack E. N.
Swallow
,
Lijin
An
,
Leanne
Jones
,
Grant
Harris
,
Peter
Bencok
,
Ronny
Sutarto
,
Jonathon P.
Cottom
,
Benjamin J.
Morgan
,
Robert A.
House
,
Robert S.
Weatherup
,
M. Saiful
Islam
Diamond Proposal Number(s):
[33062, 30644]
Open Access
Abstract: Nickelate materials offer diverse functionalities for energy and computing applications. Lithium nickel oxide (LiNiO2) is an archetypal layered nickelate, but the electronic structure of this correlated material is not yet fully understood. Here we investigate the temperature-dependent speciation and spin dynamics of Ni ions in LiNiO2. Ab initio simulations predict that Ni ions disproportionate into three states, which dynamically interconvert and whose populations vary with temperature. These predictions are verified using x-ray absorption spectroscopy, x-ray magnetic circular dichroism, and resonant inelastic x-ray scattering at the Ni L3,2-edge. Charge-transfer multiplet calculations consistent with disproportionation reproduce all experimental features. Our results support a model of dynamic disproportionation that explains diverse physical observations of LiNiO2, including magnetometry, thermally activated electronic conduction, diffractometry, core-level spectroscopies, and the stability of ubiquitous antisite defects. This unified understanding of the material properties of LiNiO2 is important for applications of nickelate materials as battery cathodes, catalysts, and superconductors.
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Oct 2025
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