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Field-induced reentrant magnetoelectric phase in LiNiPO4

Rasmus Toft-Petersen, Ellen Fogh, Takumi Kihara, Jens Jensen, Katharina Fritsch, Jooseop Lee, Garrett E. Granroth, Matthew B. Stone, David Vaknin, Hiroyuki Nojiri, Niels Bech Christensen
2017 Physical review B  
E SE = (J 12 + J 34 ) S 2 1 − 1 2 (φ 2 c + φ 2 ) − (J 34 − J 12 ) S 2 φ c φ, where φ is the field-induced change in canting angle.  ...  Assuming the linear change in exchange constants the energy difference now becomes E SE = S 2 − 0.15 − 2δφ c φ − δcos(2φ c ) 2 φ 2 .  ... 
doi:10.1103/physrevb.95.064421 fatcat:iogl4wm3xnc2je6fb35jifwsdi

Spin exchange Hamiltonian and topological degeneracies in elemental gadolinium [article]

Allen Scheie, Pontus Laurell, Paul A. McClarty, Garrett E. Granroth, Matt B. Stone, Roderich Moessner, Stephen E. Nagler
2021 arXiv   pre-print
(D1) which give an equivalent e −iQ• for a neutron scattered along (hh0).  ...  The neutron structure factor for magnetic correlations is S αβ (Q, ω) = ∞ −∞ S α 0 (0)S β (t) e −iQ• e −iωt dt, (D1) where is a sum over all neighbor distances, Q is the scattering vector, and S β r (t  ...  For E i = 100 meV the same chopper speeds were used but with the Fermi 2 chopper at 540 Hz. Appendix B: Fitting procedure  ... 
arXiv:2107.11370v3 fatcat:ayisya3dsndpnmtw5jgismvrui

Modern Trends in Neutron Scattering Instrument Technologies

Georg Ehlers, Morris L. Crow, Yacouba Diawara, Franz X. Gallmeier, Xiaosong Geng, Garrett E. Granroth, Raymond D. Gregory, Fahima F. Islam, Robert O. Knudson, Fankang Li, Matthew S. Loyd, Bogdan Vacaliuc
2022 Instruments  
However, the pulsed nature of the beam is also essential to support time-of-flight methods critical to using higher energy neutrons (E ∼ 1 eV) that cannot not be effectively monochromated with crystal  ... 
doi:10.3390/instruments6030022 fatcat:mcwu762o5veqxjqvloohrr5qoq

An NCN-pincer ligand dysprosium single-ion magnet showing magnetic relaxation via the second excited state

Yun-Nan Guo, Liviu Ungur, Garrett E. Granroth, Annie K. Powell, Chunji Wu, Stephen E. Nagler, Jinkui Tang, Liviu F. Chibotaru, Dongmei Cui
2014 Scientific Reports  
Single-molecule magnets are compounds that exhibit magnetic bistability purely of molecular origin. The control of anisotropy and suppression of quantum tunneling to obtain a comprehensive picture of the relaxation pathway manifold, is of utmost importance with the ultimate goal of slowing the relaxation dynamics within single-molecule magnets to facilitate their potential applications. Combined ab initio calculations and detailed magnetization dynamics studies reveal the unprecedented
more » ... n mediated via the second excited state within a new DyNCN system comprising a valence-localized carbon coordinated to a single dysprosium(III) ion. The essentially C 2v symmetry of the Dy III ion results in a new relaxation mechanism, hitherto unknown for mononuclear Dy III complexes, opening new perspectives for means of enhancing the anisotropy contribution to the spin-relaxation barrier.
doi:10.1038/srep05471 pmid:24969218 pmcid:PMC4073120 fatcat:5vdo6gbpunbc5hi55aiccyrp3q

Charge density wave with anomalous temperature dependence in UPt2Si2

Jooseop Lee, Karel Prokeš, Sohee Park, Igor Zaliznyak, Sachith Dissanayake, Masaaki Matsuda, Matthias Frontzek, Stanislav Stoupin, Greta L. Chappell, Ryan E. Baumbach, Changwon Park, John A. Mydosh (+2 others)
2020 Physical review B  
SF and NSF intensities from PTAX measured at 50 K at (e) Q = (2 0.42 0) and (f) (2 1.58 0), where solid lines are fit to a Gaussian. . 1(b) and 1(c), the intensities of longitudinal superlattice peaks  ...  investigated the origin of these superlattice reflections by performing neutron polarization analysis on the (2 0.42 0) and (2 1.58 0) satellite peaks at 50 K at HB1 triple-axis spectrometer as shown in Figs. 1(e)  ... 
doi:10.1103/physrevb.102.041112 fatcat:ll2rynm4ojfo3p53nqdhp5mesa

Dirac magnons, nodal lines, and nodal plane in elemental gadolinium [article]

Allen Scheie, Pontus Laurell, Paul A. McClarty, Garrett E. Granroth, Matt B. Stone, Roderich Moessner, Stephen E. Nagler
2021 arXiv   pre-print
ick z e iakx 2 + e 1 2 ia 2k x + √ 3k y + e 1 2 i √ 3ak y × e − 1 6 i 3ck z +3ak x +2 √ 3ak y , (S16) γ 3 = 1 6 1 + e ick z e 2iak x + e ia k x + √ 3k y + 1 × e − 1 6 i 3ck z +6ak x +2 √ 3ak y .  ...  For E i = 100 meV we ran the same configuration but Fermi 2 chopper at 540 Hz.  ... 
arXiv:2107.11372v3 fatcat:cro4zomiwjdwxkmxpr7y744pjy

Recent developments of MCViNE and its applications at SNS

Jiao Lin, Fahima Islam, Gabriele Sala, Ian Lumsden, Hillary Smith, Mathieu Doucet, Matthew B Stone, Douglas L Abernathy, Georg Ehlers, John F. Ankner, Garrett E Granroth
2019 Journal of Physics Communications  
Figure 3 (C) shows a S(Q,E) spectrum obtained from simulation.  ...  (B) Energy spectrum obtained from integrating the I(Q, E) spectrum in (A) over Q range of 5-9Å −1 .  ... 
doi:10.1088/2399-6528/ab3622 fatcat:it6balaj25hulaw3jwofkpatzi

Spin dynamics of the low-dimensional magnet (CH3)2NH2CuCl3

Matthew B. Stone, Wei Tian, Garrett E. Granroth, Mark D. Lumsden, J.-H. Chung, David G. Mandrus, Stephen E. Nagler
2006 Physica. B, Condensed matter  
Dimethylammonium copper (II) chloride (also known as DMACuCl3 or MCCL) is a low dimensional S=1/2 quantum spin system proposed to be an alternating ferro-antiferromagnetic chain with similar magnitude ferromagnetic (FM) and antiferromagnetic (AFM) exchange interactions. Subsequently, it was shown that the existing bulk measurements could be adequately modeled by considering DMACuCl3 as independent AFM and FM dimer spin pairs. We present here new inelastic neutron scattering measurements of the
more » ... pin-excitations in single crystals of DMACuCl3. These results show significant quasi-one-dimensional coupling, however the magnetic excitations do not propagate along the expected direction. We observe a band of excitations with a gap of 0.95 meV and a bandwidth of 0.82 meV.
doi:10.1016/j.physb.2006.05.145 fatcat:5bk7yattyfgmfdbvjzp6tgoqjy

Dual Nature of Magnetism in a Uranium Heavy-Fermion System

Jooseop Lee, Masaaki Matsuda, John A. Mydosh, Igor Zaliznyak, Alexander I. Kolesnikov, Stefan Süllow, Jacob P. C. Ruff, Garrett E. Granroth
2018 Physical Review Letters  
While data with E i ¼ 50 meV reveal the 7 meV gap with better resolution, E i ¼ 100 meV data capture the full range of magnetic excitation and, therefore, were used for the global fitting.  ...  The measured scattering intensities were converted to the imaginary part of the dynamical magnetic susceptibility via the fluctuationdissipation theorem, χ 00 ðQ;ωÞ ¼ πð1 − eE=k B T ÞSðQ;ωÞ [20] .  ... 
doi:10.1103/physrevlett.121.057201 pmid:30118279 fatcat:hf24odgifngofg5awb2xkqpheu

Strongly two-dimensional exchange interactions in the in-plane metallic antiferromagnet Fe_2As probed by inelastic neutron scattering [article]

Manohar H. Karigerasi, Kisung Kang, Garrett E. Granroth, Arnab Banerjee, André Schleife, Daniel P. Shoemaker
2020 arXiv   pre-print
Karigerasi, Kisung Kang, Garrett E. Granroth, Arnab Banerjee, André Schleife, Daniel P.  ...  Data from E i = 30 meV (below dashed lines) has been overlaid on top of data from E i = 70 meV. The corresponding simulated phonon spectra along [0 1 L] is shown in (b).  ... 
arXiv:2008.05050v1 fatcat:uqgclh45kna75knax6vrgeoxma

Event-based processing of neutron scattering data at the Spallation Neutron Source

Garrett E. Granroth, Ke An, Hillary L. Smith, Pamela Whitfield, Joerg C. Neuefeind, Jooseop Lee, Wenduo Zhou, Vladislav N. Sedov, Peter F. Peterson, Andre Parizzi, Harley Skorpenske, Steven M. Hartman (+2 others)
2018 Journal of Applied Crystallography  
Cryst. (2018). 51, 616-629 Garrett E. Granroth et al. Event-based processing of neutron data 621 E. Granroth et al. Event-based processing of neutron data J. Appl.  ...  Cryst. (2018). 51, 616-629 Garrett E. Granroth et al. Event-based processing of neutron data 623 E. Granroth et al. Event-based processing of neutron data J. Appl.  ... 
doi:10.1107/s1600576718004727 fatcat:ko5pth26mvgkhodyoytf6lp3ti

Charge density wave with anomalous temperature dependence in UPt2Si2 [article]

Jooseop Lee, Karel Prokes, Sohee Park, Igor Zaliznyak, Sachith Dissanayake, Masaaki Matsuda, Matthias Frontzek, Stanislav Stoupin, Greta L. Chappell, Ryan E. Baumbach, Changwon Park, John A. Mydosh (+2 others)
2020 arXiv   pre-print
SF and NSF intensities from PTAX measured at 50 K at (e) Q = (2 0.42 0) and (f) (2 1.58 0), where solid lines are fit to a Gaussian.  ...  the origin of these superlattice reflections by performing neutron polarization analysis on the (2 0.42 0) and (2 1.58 0) satellite peaks at 50 K at HB1 triple-axis spectrometer as shown in Fig. 1 (e)  ... 
arXiv:1908.03160v4 fatcat:5test3cqprattigo3qtuiktupq

Electronic and structural properties of RbCeX_2 (X_2: O_2, S_2, SeS, Se_2, TeSe, Te_2) [article]

Brenden R. Ortiz, Mitchell M. Bordelon, Pritam Bhattacharyya, Ganesh Pokharel, Paul M. Sarte, Lorenzo Posthuma, Thorben Petersen, Mohamed S. Eldeeb, Garrett E. Granroth, Clarina R. Dela Cruz, Stuart Calder, Douglas L. Abernathy (+2 others)
2022 arXiv   pre-print
E.  ...  2 , and E 1 =27.5, E 2 =34.1 meV for RbCeTe 2 .  ... 
arXiv:2204.12086v2 fatcat:mrtwmusjdfbsjdqmzabvvyqqxu

MCViNE – An object oriented Monte Carlo neutron ray tracing simulation package

Jiao Y.Y. Lin, Hillary L. Smith, Garrett E. Granroth, Douglas L. Abernathy, Mark D. Lumsden, Barry Winn, Adam A. Aczel, Michael Aivazis, Brent Fultz
2016 Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment  
structure factor S(Q, E) = 1 − γ Q // 2 1 − γ 2 Q // δ(EE(Q)) (2) where γ Q // = cos(hπ) cos(kπ), 2J = 2.563.  ...  In (e), all of the kernels in (d) are used with multiple scattering turned on. Overall the features shown in the experiment data (a) and the simulated data (e) agree very well.  ... 
doi:10.1016/j.nima.2015.11.118 fatcat:yduqzcsqh5ghhfta522zu6v6gm

Spinon Fermi surface spin liquid in a triangular lattice antiferromagnet NaYbSe_2 [article]

Peng-Ling Dai, Gaoning Zhang, Yaofeng Xie, Chunruo Duan, Yonghao Gao, Zihao Zhu, Erxi Feng, Zhen Tao, Chien-Lung Huang, Huibo Cao, Andrey Podlesnyak, Garrett E. Granroth (+11 others)
2021 arXiv   pre-print
The wave vector cuts in (a,b,d-g) were measured in the [H, H, L] zone with E i = 3.32 meV, while those in (c,h,i) were measured in the [H, K, 0] plane with E i = 3.70 meV.  ...  To excite the pair with an energy E, a minimal momentum transfer E/v F is needed where v F is the Fermi velocity. The slope of the V-shape is expected to be the Fermi velocity.  ... 
arXiv:2004.06867v4 fatcat:p5jfhj6uvffvti6w5a45rd7drm
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