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BACKGROUND: Osteofibrous dysplasia-like adamantinoma (OFD-AD) and classic adamantinoma (AD) are rare, neoplastic diseases with only limited data supporting current treatment protocols. We believe that our retrospective multicenter cohort study is the largest analysis of patients with adamantinoma to date. The primary purpose of this study was to describe the disease characteristics and evaluate the oncological outcomes. The secondary purpose was to identify risk factors for local recurrence after surgical treatment and propose treatment guidelines. METHODS: Three hundred and eighteen confirmed cases of OFD-AD and AD for which primary treatment was carried out between 1985 and 2015 were submitted by 22 tertiary bone tumor centers. Proposed clinical risk factors for local recurrence such as size, type, and margins were analyzed using univariable and multivariate Cox regression analysis. RESULTS: Of the 318 cases, 128 were OFD-AD and 190 were AD. The mean age at diagnosis was 17 years (median, 14.5 years) for OFD-AD and 32 years (median, 28 years) for AD; 53% of the patients were female. The mean tumor size in the OFD-AD and AD groups combined was 7.8 cm, measured histologically. Sixteen percent of the patients sustained a pathological fracture prior to treatment. Local recurrence was recorded in 22% of the OFD-AD cases and 24% of the AD cases. None of the recurrences in the OFD-AD group progressed to AD. Metastatic disease was found in 18% of the AD cases and fatal disease, in 11% of the AD cases. No metastatic or fatal disease was reported in the OFD-AD group. Multivariate Cox regression analysis demonstrated that uncontaminated resection margins (hazard ratio [HR] = 0.164, 95% confidence interval [CI] = 0.092 to 0.290, p < 0.001), pathological fracture (HR = 1.968, 95% CI = 1.076 to 3.600, p = 0.028), and sex (female versus male: HR = 0.535, 95% CI = 0.300 to 0.952, p = 0.033) impacted the risk of local recurrence. CONCLUSIONS: OFD-AD and AD are parts of a disease spectrum but should be regarded as different entities. Our results support reclassification of OFD-AD into the intermediate locally aggressive category, based on the local recurrence rate of 22% and absence of metastases. In our study, metastatic disease was restricted to the AD group (an 18% rate). We advocate wide resection with uncontaminated margins including bone and involved periosteum for both OFD-AD and AD. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
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Adamantinoma/cirurgia , Doenças do Desenvolvimento Ósseo/cirurgia , Neoplasias Ósseas/cirurgia , Adamantinoma/patologia , Adolescente , Adulto , Doenças do Desenvolvimento Ósseo/patologia , Neoplasias Ósseas/patologia , Feminino , Humanos , Masculino , Recidiva Local de Neoplasia , Prognóstico , Fatores de Risco , Resultado do TratamentoRESUMO
Sub-picosecond magnetisation manipulation via femtosecond optical pumping has attracted wide attention ever since its original discovery in 1996. However, the spatial evolution of the magnetisation is not yet well understood, in part due to the difficulty in experimentally probing such rapid dynamics. Here, we find evidence of a universal rapid magnetic order recovery in ferrimagnets with perpendicular magnetic anisotropy via nonlinear magnon processes. We identify magnon localisation and coalescence processes, whereby localised magnetic textures nucleate and subsequently interact and grow in accordance with a power law formalism. A hydrodynamic representation of the numerical simulations indicates that the appearance of noncollinear magnetisation via optical pumping establishes exchange-mediated spin currents with an equivalent 100% spin polarised charge current density of 107 A cm-2. Such large spin currents precipitate rapid recovery of magnetic order after optical pumping. The magnon processes discussed here provide new insights for the stabilization of desired meta-stable states.
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Using ultrafast ≃2.5 fs and ≃25 fs self-amplified spontaneous emission pulses of increasing intensity and a novel experimental scheme, we report the concurrent increase of stimulated emission in the forward direction and loss of out-of-beam diffraction contrast for a Co/Pd multilayer sample. The experimental results are quantitatively accounted for by a statistical description of the pulses in conjunction with the optical Bloch equations. The dependence of the stimulated sample response on the incident intensity, coherence time, and energy jitter of the employed pulses reveals the importance of increased control of x-ray free electron laser radiation.
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"The technical support from SLAC Accelerator Directorate, Technology Innovation Directorate, LCLS laser division and Test Facility Division is gratefully acknowledged. We thank S.P. Weathersby, R.K. Jobe, D. McCormick, A. Mitra, S. Carron and J. Corbett for their invaluable help and technical assistance. Research at SLAC was supported through the SIMES Institute which like the LCLS and SSRL user facilities is funded by the Office of Basic Energy Sciences of the U.S. Department of Energy under Contract No. DE-AC02-76SF00515. The UED work was performed at SLAC MeV-UED, which is supported in part by the DOE BES SUF Division Accelerator & Detector R&D program, the LCLS Facility, and SLAC under contract Nos. DE-AC02-05-CH11231 and DE-AC02-76SF00515. Use of the Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515."and"Work at BNL was supported by DOE BES Materials Science and Engineering Division under Contract No: DE-AC02-98CH10886. J.C. would like to acknowledge the support from National Science Foundation Grant No. 1207252. E.E.F. would like to acknowledge support from the U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES) under Award No. DE-SC0003678."This has been corrected in both the PDF and HTML versions of the Article.
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Magnetostriction, the strain induced by a change in magnetization, is a universal effect in magnetic materials. Owing to the difficulty in unraveling its microscopic origin, it has been largely treated phenomenologically. Here, we show how the source of magnetostriction-the underlying magnetoelastic stress-can be separated in the time domain, opening the door for an atomistic understanding. X-ray and electron diffraction are used to separate the sub-picosecond spin and lattice responses of FePt nanoparticles. Following excitation with a 50-fs laser pulse, time-resolved X-ray diffraction demonstrates that magnetic order is lost within the nanoparticles with a time constant of 146 fs. Ultrafast electron diffraction reveals that this demagnetization is followed by an anisotropic, three-dimensional lattice motion. Analysis of the size, speed, and symmetry of the lattice motion, together with ab initio calculations accounting for the stresses due to electrons and phonons, allow us to reveal the magnetoelastic stress generated by demagnetization.
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We apply time-resolved MeV electron diffraction to study the electron-lattice energy relaxation in thin film Au-insulator heterostructures. Through precise measurements of the transient Debye-Waller-factor, the mean-square atomic displacement is directly determined, which allows to quantitatively follow the temporal evolution of the lattice temperature after short pulse laser excitation. Data obtained over an extended range of laser fluences reveal an increased relaxation rate when the film thickness is reduced or the Au-film is capped with an additional insulator top-layer. This behavior is attributed to a cross-interfacial coupling of excited electrons in the Au film to phonons in the adjacent insulator layer(s). Analysis of the data using the two-temperature-model taking explicitly into account the additional energy loss at the interface(s) allows to deduce the relative strength of the two relaxation channels.
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Transitions between different charge density wave (CDW) states in quasi-two-dimensional materials may be accompanied also by changes in the inter-layer stacking of the CDW. Using MeV ultrafast electron diffraction, the out-of-plane stacking order dynamics in the quasi-two-dimensional dichalcogenide 1T-TaS2 is investigated for the first time. From the intensity of the CDW satellites aligned around the commensurate l = 1/6 characteristic stacking order, it is found out that this phase disappears with a 0.3 ps time constant. Simultaneously, in the same experiment, the emergence of the incommensurate phase, with a slightly slower 2.0 ps time constant, is determined from the intensity of the CDW satellites aligned around the incommensurate l = 1/3 characteristic stacking order. These results might be of relevance in understanding the metallic character of the laser-induced metastable "hidden" state recently discovered in this compound.
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Intraarticular benign tumors are rare lesions in many cases seen as incidental findings. One of the typical lesions is the diffuse or nodular form of pigmented villonodular synovitis, which needs a complete surgical removal. Magnetic Resonance Imaging (MRI) is diagnostic in most of the cases because of the intracellular iron content which shows an at least in some parts dark T2-sequence. Adjuvant therapies as radiosynoviorthesis should be considered in diffuse or recurrent lesions. Synovial Chondromatosis represents a metaplastic disorder of the synovial membrane resulting in the production of loose cartilage bodies. Also in this dissease synovectomy or, in late cases, removal of the loose bodies only, is recommended. Synovial hemangiomas are hamartomas which may lead to pain or restriction of movement. In these cases total or partial resection is justified. Alternative treatment options such as laserablation may be possible. Lipoma arborescens represents a proliferative lipoid lesion of the subsynovial region leading to villonodular synovial proliferation. If clinically symptomatic, resection by arthroscopic or open synovectomy is recommented.
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Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/cirurgia , Artropatias/diagnóstico , Artropatias/cirurgia , Artroscopia , Neoplasias Ósseas/patologia , Condromatose Sinovial/diagnóstico , Condromatose Sinovial/patologia , Condromatose Sinovial/cirurgia , Diagnóstico Diferencial , Hemangioma/diagnóstico , Hemangioma/patologia , Hemangioma/cirurgia , Humanos , Artropatias/patologia , Lipoma/diagnóstico , Lipoma/patologia , Lipoma/cirurgia , Imageamento por Ressonância Magnética , Sinovite Pigmentada Vilonodular/diagnóstico , Sinovite Pigmentada Vilonodular/patologia , Sinovite Pigmentada Vilonodular/cirurgiaRESUMO
We use single-cycle THz fields and the femtosecond magneto-optical Kerr effect to, respectively, excite and probe the magnetization dynamics in two thin-film ferromagnets with different lattice structures: crystalline Fe and amorphous CoFeB. We observe Landau-Lifshitz-torque magnetization dynamics of comparable magnitude in both systems, but only the amorphous sample shows ultrafast demagnetization caused by the spin-lattice depolarization of the THz-induced ultrafast spin current. Quantitative modeling shows that such spin-lattice scattering events occur on similar time scales than the conventional spin conserving electronic scattering (â¼30 fs). This is significantly faster than optical laser-induced demagnetization. THz conductivity measurements point towards the influence of lattice disorder in amorphous CoFeB as the driving force for enhanced spin-lattice scattering.
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X-ray diffractive imaging with laterally coherent x-ray free-electron laser (XFEL) pulses is increasingly utilized to obtain ultrafast snapshots of matter. Here we report the amazing disappearance of single-shot charge and magnetic diffraction patterns recorded with resonantly tuned, narrow bandwidth XFEL pulses. Our experimental results reveal the exquisite sensitivity of single-shot charge and magnetic diffraction patterns of a magnetic film to the onset of field-induced stimulated elastic x-ray forward scattering. The loss in diffraction contrast, measured over 3 orders of magnitude in intensity, is in remarkable quantitative agreement with a recent theory that is extended to include diffraction.
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We use polarization- and temperature-dependent x-ray absorption spectroscopy, in combination with photoelectron microscopy, x-ray diffraction, and electronic transport measurements, to study the driving force behind the insulator-metal transition in VO_{2}. We show that both the collapse of the insulating gap and the concomitant change in crystal symmetry in homogeneously strained single-crystalline VO_{2} films are preceded by the purely electronic softening of Coulomb correlations within V-V singlet dimers. This process starts 7 K (±0.3 K) below the transition temperature, as conventionally defined by electronic transport and x-ray diffraction measurements, and sets the energy scale for driving the near-room-temperature insulator-metal transition in this technologically promising material.
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Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no direct experimental observation exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50 ps temporal resolution and 35 nm spatial resolution, we are able to create a real-space spin-wave movie and observe the emergence of a localized soliton with a nodal line, that is, with p-like symmetry. Micromagnetic simulations explain the measurements and reveal that the symmetry of the soliton can be controlled by magnetic fields. Our results broaden the understanding of spin-wave dynamics at the nanoscale, with implications for the design of magnetic nanodevices.
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We have used a MHz lock-in x-ray spectromicroscopy technique to directly detect changes in magnetic moment of Cu due to spin injection from an adjacent Co layer. The elemental and chemical specificity of x rays allows us to distinguish two spin current induced effects. We detect the creation of transient magnetic moments of 3×10^{-5}µ_{B} on Cu atoms within the bulk of the 28 nm thick Cu film due to spin accumulation. The moment value is compared to predictions by Mott's two current model. We also observe that the hybridization induced existing magnetic moments at the Cu interface atoms are transiently increased by about 10% or 4×10^{-3}µ_{B} per atom. This reveals the dominance of spin-torque alignment over Joule heat induced disorder of the interfacial Cu moments during current flow.
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Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.
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INTRODUCTION: Limb-sparing surgery is considered as first choice in most patients with soft tissue sarcomas of the extremities. 5-year survival rates after limb soft tissue sarcoma resection have been promising in many specalised interdisciplinary centres. Quality of life as well as extremity function have thus become an integral aspect of the surgical management of soft tissue sarcomas of the extremities. OBJECTIVE: We herein report on our experience in the anatomic reconstruction of the extremities following limb-sparing soft tissue sarcoma resection using microvascular gracilis muscle flap and skin grafts. PATIENTS AND METHODS: Between 2012 and 2014 an anatomic reconstruction of the hand and foot using gracilis muscle flaps following limb-sparing sarcoma resection (leiomyosarcoma N=2, myxofibrosarcoma N=2, clear cell sarcoma N=1, myxoinflammatory fibroblastic sarcoma N=1, granular cell tumour N=1, pleomorphic sarcoma N=1) was performed in N=8 patients (4 females, 4 males), average age: 44 years (23-76 years), average follow-up time 444 days (98-820). RESULTS: In all patients successful defect coverage with unimpaired wound healing was achieved (adjunctive radiotherapy n=4). The tendon of the harvested gracilis muscle was used for anatomic reconstruction of consequently resected essential anatomic structures (extensor retinaculum n=1, flexor/extensor tendons n=4, extensor expansion n=2, tendon reinsertion n=1, proximal interphalangeal joint collateral ligament n=4, dorsal metatarsal ligament n=1). During follow-up neither local recurrence nor metastasis was observed. CONCLUSION: Reconstruction of multidirectional stability as well as restoring biomechanics and kinetics of the hand and foot should be considered during defect coverage and dead space obliteration management after sarcoma resection of the extremities. For reasons of sound options in anatomic extremity reconstruction with minimal donor site morbidity, the gracilis muscle flap excels in the field of limb-sparing sarcoma resection.
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Pé/cirurgia , Mãos/cirurgia , Salvamento de Membro/métodos , Microcirurgia/métodos , Retalho Miocutâneo/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Adulto , Idoso , Feminino , Pé/irrigação sanguínea , Mãos/irrigação sanguínea , Humanos , Ligamentos/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Retalho Miocutâneo/irrigação sanguínea , Estudos Retrospectivos , Sarcoma/diagnóstico , Sarcoma/patologia , Transplante de Pele/métodos , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/patologiaRESUMO
BACKGROUND: In multimodal therapy concepts for bone sarcomas, tumor resection is a deciding factor. Modern imaging techniques have made preoperative resection planning much easier and precisely allow tumor boundaries to be defined. OBJECTIVES: There is recent data clearly showing that compartmental resections have no significant advantages compared to wide resections in terms of local recurrence or overall survival. But it remains unclear, how "wide" a "wide resection" should be done. MATERIALS AND METHODS: A literature review of the last 15 years, discussion of review articles and multidisciplinary expert opinions as published in major multinational studies. RESULTS: Intralesional resection (R1) is feasible in highly differentiated (G1) chondrosarcoma (atypical cartilaginous tumor) of the extremity. In both osteosarcoma and Ewing's sarcoma, R0 resection is mandatory. If these fails, there is evidence that in selected cases of osteosarcoma, adjuvant radiotherapy is justified if a second resection is not possible. Expecting contaminated (R1) margins in patients with Ewing's sarcoma (e.g., in critical locations such as the pelvis), radiotherapy only is better than hoping for the "cure" of insufficient resections margins with a combination of both methods. With regard to the necessary safety distances for a R0 resection, recommendations from the literature are heterogeneous. In addition to the distance measurement, the quality of the anatomic resection margins (e.g., fascia) is of great importance. A distinct recommendation of at least x millimeters or centimeters cannot be given based on the currently available data. CONCLUSION: The aim of the resection of a bone sarcoma should be a wide margin with the exception of chondrosarcoma (G1). Ultraradical resections which sacrifice vital structures in order to extend an already wide (R0) resection margin showed no significant benefits. In patients with osteosarcoma, adjuvant radiotherapy should be considered if resection or re-resection is not in sound tissue (R1). Patients with Ewing's sarcoma should not undergo resection if a contaminated margin is expected. In patients with chondrosarcoma, the available data as for example from pelvic tumors are contradictory and do not allow a clear recommendation.
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Algoritmos , Neoplasias Ósseas/patologia , Neoplasias Ósseas/terapia , Recidiva Local de Neoplasia/prevenção & controle , Osteossarcoma/patologia , Osteossarcoma/terapia , Osteotomia/métodos , Terapia Combinada/métodos , Medicina Baseada em Evidências , Humanos , Recidiva Local de Neoplasia/patologia , Neoplasia Residual , Prognóstico , Resultado do Tratamento , Carga TumoralRESUMO
BACKGROUND: The overall survival in patients with typical bone sarcomas such as Ewing-sarcoma, osteosarcoma, or chondrosarcoma exceeds 60% in localized disease after 5 years. Local or systemic recurrence detected by surveillance may not only improve or solve the local problem but also significantly improves the prognosis of the patient. Thus, surveillance seems to be justified. OBJECTIVES: As a consequence, the questions of how and how long surveillance should be performed must be answered. METHODS: A literature review of the last 15 years, discussion of review articles, and multidisciplinary expert opinions as published in major multinational studies. RESULTS: The decision which surveillance scheme outside of clinical studies might be appropriate largely depends on the prognostic benefit of early detection of local or systemic recurrence. The detection rate of local recurrence by the patient himself is high in extremities. A systematic technical examination for the detection of pulmonary metastases is controversial because the chance of cure in systemic progression is generally unfavorable. Whether the earlier detection of both types of recurrence due to reduced examination intervals and/or the use of a CT or MRI is significantly advantageous, remains unproven. The duration of surveillance is even less clear. Both local and systemic recurrences may be seen more than 10 years after treatment of the primary tumor. CONCLUSION: Surveillance makes sense in any case, since the detection of a local recurrence is possible already with methods easy to apply. Whether and to what extent local imaging is used is left to the individual case. Under the current conditions in Germany, local (e.g., MRI) imaging at least every 6 months during the first 2-3 years, then possibly on an annual basis is recommended. There is no evidence-based support for the decision whether and when an X-ray of the chest is indicated and whether and when a CT scan should be performed. Striking is the lack of prospective studies on surveillance concerning both patient- and economically relevant aspects of tumor therapy.
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Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/terapia , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/prevenção & controle , Osteossarcoma/diagnóstico , Osteossarcoma/terapia , Vigilância de Evento Sentinela , Neoplasias Ósseas/mortalidade , Medicina Baseada em Evidências , Humanos , Recidiva Local de Neoplasia/mortalidade , Osteossarcoma/mortalidade , Prevalência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taxa de Sobrevida , Fatores de TempoRESUMO
Patients with high-risk soft tissue sarcomas (FNCLCC grades 2-3, > 5 cm and deep lying) are at a high risk of local recurrence or distant metastases despite optimal surgical tumor resection. Therefore, multimodal treatment should be considered for this difficult to treat patient group. Besides surgery, radiation therapy and chemotherapy, hyperthermia has become a valid, complementary treatment option within multimodal treatment concepts. Hyperthermia in this context means the selective heating of the tumor region to temperatures of 40-43 °C for 60 min by microwave radiation in addition to simultaneous chemotherapy or radiation therapy. A randomized phase III study demonstrated that the addition of hyperthermia to neoadjuvant chemotherapy improved tumor response and was associated with a minimal risk of early disease progression as compared to chemotherapy alone. The addition of hyperthermia to a multimodal treatment regimen for high-risk soft tissue sarcoma consisting of surgery, radiation therapy and chemotherapy, either in the neoadjuvant or adjuvant setting after incomplete or marginal tumor resection, significantly improved local progression-free and disease-free survival. Based on these results and due to the generally good tolerability of hyperthermia, this treatment method in combination with chemotherapy should be considered as a standard treatment option within multimodal treatment approaches for locally advanced high-risk soft tissue sarcoma.
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Hipertermia Induzida , Sarcoma/patologia , Sarcoma/terapia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/terapia , Quimioterapia Adjuvante , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Humanos , Terapia Neoadjuvante , Gradação de Tumores , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Prognóstico , Radioterapia Adjuvante , Ensaios Clínicos Controlados Aleatórios como Assunto , Sarcoma/mortalidade , Neoplasias de Tecidos Moles/mortalidadeRESUMO
As the oldest known magnetic material, magnetite (Fe3O4) has fascinated mankind for millennia. As the first oxide in which a relationship between electrical conductivity and fluctuating/localized electronic order was shown, magnetite represents a model system for understanding correlated oxides in general. Nevertheless, the exact mechanism of the insulator-metal, or Verwey, transition has long remained inaccessible. Recently, three-Fe-site lattice distortions called trimerons were identified as the characteristic building blocks of the low-temperature insulating electronically ordered phase. Here we investigate the Verwey transition with pump-probe X-ray diffraction and optical reflectivity techniques, and show how trimerons become mobile across the insulator-metal transition. We find this to be a two-step process. After an initial 300 fs destruction of individual trimerons, phase separation occurs on a 1.5±0.2 ps timescale to yield residual insulating and metallic regions. This work establishes the speed limit for switching in future oxide electronics.
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Ultrafast laser techniques have revealed extraordinary spin dynamics in magnetic materials that equilibrium descriptions of magnetism cannot explain. Particularly important for future applications is understanding non-equilibrium spin dynamics following laser excitation on the nanoscale, yet the limited spatial resolution of optical laser techniques has impeded such nanoscale studies. Here we present ultrafast diffraction experiments with an X-ray laser that probes the nanoscale spin dynamics following optical laser excitation in the ferrimagnetic alloy GdFeCo, which exhibits macroscopic all-optical switching. Our study reveals that GdFeCo displays nanoscale chemical and magnetic inhomogeneities that affect the spin dynamics. In particular, we observe Gd spin reversal in Gd-rich nanoregions within the first picosecond driven by the non-local transfer of angular momentum from larger adjacent Fe-rich nanoregions. These results suggest that a magnetic material's microstructure can be engineered to control transient laser-excited spins, potentially allowing faster (~ 1 ps) spin reversal than in present technologies.