Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

Selected Works

Condensed Matter Physics

Deborah L. Schlagel

Articles 1 - 6 of 6

Full-Text Articles in Physics

Slowing Down Of Spin Glass Correlation Length Growth: Simulations Meet Experiments, Qiang Zhai, V. Martin-Mayor, Deborah L. Schlagel, Gregory G. Kenning, Raymond L. Orbach Oct 2019

Slowing Down Of Spin Glass Correlation Length Growth: Simulations Meet Experiments, Qiang Zhai, V. Martin-Mayor, Deborah L. Schlagel, Gregory G. Kenning, Raymond L. Orbach

Deborah L. Schlagel

The growth of the spin glass correlation length has been measured as a function of the waiting time tw on a single crystal of CuMn (6 at. %), reaching values ξ∼150 nm, larger than any other glassy correlation length measured to date. We find an aging rate dlntw/dlnξ larger than found in previous measurements, which evinces a dynamic slowing down as ξ grows. Our measured aging rate is compared with simulation results by the Janus Collaboration. After critical effects are taken into account, we find excellent agreement with the Janus data.


Skyrmions And Spirals In Mnsi Under Hydrostatic Pressure, L. J. Bannenberg, R. Sadykov, R. M. Dalgliesh, C. Goodway, Deborah L. Schlagel, Thomas A. Lograsso, P. Falus, E. Lelièvre-Berna, A. O. Leonov, C. Pappas Oct 2019

Skyrmions And Spirals In Mnsi Under Hydrostatic Pressure, L. J. Bannenberg, R. Sadykov, R. M. Dalgliesh, C. Goodway, Deborah L. Schlagel, Thomas A. Lograsso, P. Falus, E. Lelièvre-Berna, A. O. Leonov, C. Pappas

Deborah L. Schlagel

The archetype cubic chiral magnet MnSi is home to some of the most fascinating states in condensed matter, such as skyrmions and a non-Fermi-liquid behavior in conjunction with a topological Hall effect under hydrostatic pressure. Using small angle neutron scattering, we study the evolution of the helimagnetic, conical, and skyrmionic correlations with increasing hydrostatic pressure. We show that the helical propagation vector smoothly reorients from ⟨111⟩ to ⟨100⟩ at intermediate pressures. At higher pressures, above the critical pressure, the long-range helimagnetic order disappears at zero magnetic field. Nevertheless, skyrmion lattices and conical spirals form under magnetic fields, in a part ...


Two-Dimensional Ordering And Collective Magnetic Excitations In The Dilute Ferromagnetic Topological Insulator (Bi0.95 Mn0.05)2 Te3, David Vaknin, Daniel M. Pajerowski, Deborah L. Schlagel, Kevin W. Dennis, Robert Mcqueeney Jul 2019

Two-Dimensional Ordering And Collective Magnetic Excitations In The Dilute Ferromagnetic Topological Insulator (Bi0.95 Mn0.05)2 Te3, David Vaknin, Daniel M. Pajerowski, Deborah L. Schlagel, Kevin W. Dennis, Robert Mcqueeney

Deborah L. Schlagel

Employing elastic and inelastic neutron scattering (INS) techniques, we report on the microscopic properties of the ferromagnetism in the dilute magnetic topological insulator (Bi0.95Mn0.05)2 Te3. Neutron diffraction of polycrystalline samples shows the ferromagnetic (FM) ordering is long range within the basal plane, and mainly two dimensional (2D) in character with short-range correlations between layers below T C ≈ 13 K. Remarkably, we observe gapped and collective magnetic excitations in this dilute magnetic system. The excitations appear typical of quasi-2D FM systems despite the severe broadening of short-wavelength magnons which is expected from the random spatial distribution of Mn ...


Suppression Of Antiferromagnetic Spin Fluctuations In Superconducting Cr0.8 Ru0.2, M. Ramazanoglu, Benjamin G. Ueland, D. K. Pratt, L. W. Harringer, J. W. Lynn, G. Ehlers, G. E. Granroth, Sergey L. Bud’Ko, Paul C. Canfield, Deborah L. Schlagel, Alan I. Goldman, Thomas A. Lograsso, Robert J. Mcqueeney Jul 2019

Suppression Of Antiferromagnetic Spin Fluctuations In Superconducting Cr0.8 Ru0.2, M. Ramazanoglu, Benjamin G. Ueland, D. K. Pratt, L. W. Harringer, J. W. Lynn, G. Ehlers, G. E. Granroth, Sergey L. Bud’Ko, Paul C. Canfield, Deborah L. Schlagel, Alan I. Goldman, Thomas A. Lograsso, Robert J. Mcqueeney

Deborah L. Schlagel

Unconventional superconductivity (SC) often develops in magnetic metals on the cusp of static antiferromagnetic (AFM) order where spin fluctuations are strong. This association is so compelling that many SC materials are labeled as unconventional by proximity to an ordered AFM state. The Cr-Ru alloy system possesses such a phase diagram [see Fig. 1(a)]. Here we use inelastic neutron scattering to show that spin fluctuations are present in a SC Cr0.8Ru0.2 alloy (Tc=1.35 K). However, the neutron spin resonance, a possible signature of unconventional SC, is not observed. Instead, data indicate a spin gap of order ...


17o And 51v Nmr For The Zigzag Spin-1 Chain Compound Cav2o4, X. Zong, B. J. Suh, A. Niazi, J.-Q. Yan, Deborah L. Schlagel, Thomas A. Lograsso, David C. Johnston Aug 2014

17o And 51v Nmr For The Zigzag Spin-1 Chain Compound Cav2o4, X. Zong, B. J. Suh, A. Niazi, J.-Q. Yan, Deborah L. Schlagel, Thomas A. Lograsso, David C. Johnston

Deborah L. Schlagel

51V NMR studies on CaV2O4 single crystals and 17O NMR studies on 17O-enriched powder samples are reported. The temperature dependences of the 17O NMR linewidth and nuclear spin-lattice relaxation rate give strong evidence for a long-range antiferromagnetic transition at TN=78 K in the powder. Magnetic susceptibility measurements show that TN=69 K in the crystals. A zero-field 51V NMR signal was observed at low temperatures (f≈237 MHz at 4.2 K) in the crystals. The field-swept spectra with the field in different directions suggest the presence of two antiferromagnetic substructures. Each substructure is collinear, with the easy axes ...


Relation Between Ga Ordering And Magnetostriction Of Fe-Ga Alloys Studied By X-Ray Diffuse Scattering, Y. Du, Mianliang Huang, S. Chang, Deborah L. Schlagel, Thomas A. Lograsso, Robert J. Mcqueeney Aug 2014

Relation Between Ga Ordering And Magnetostriction Of Fe-Ga Alloys Studied By X-Ray Diffuse Scattering, Y. Du, Mianliang Huang, S. Chang, Deborah L. Schlagel, Thomas A. Lograsso, Robert J. Mcqueeney

Deborah L. Schlagel

Transmission synchrotron diffraction was employed to characterize the Ga ordering in magnetostrictive Fe100−xGax alloys with Ga concentrations from 0 to 20.3 at. %. The experiments focused on the development of atomic short-range ordering (SRO) by analysis of the diffuse scattering appearing at superlattice positions of the D03 ordered alloy structure. No SRO was found for Ga concentrations less than 4 at. %. Between 13 and 20.3 at. %, D03-type SRO clusters are observed whose size increases with Ga concentration for both slow-cooled and quenched samples. Thermal quenching of the samples suppresses the cluster sizes when compared to slow-cooled samples of ...