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相关论文: Magnetocaloric effect in pyrochlore antiferromagne…

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We study the finite-temperature transition in a model XY antiferromagnet on a pyrochlore lattice, which describes the pyrochlore material Er2Ti2O7. The ordered magnetic structure selected by thermal fluctuations is six-fold degenerate.…

强关联电子 · 物理学 2014-04-15 M. E. Zhitomirsky , P. C. W. Holdsworth , R. Moessner

Using muon-spin-relaxation measurements we show that the pyrochlore compound Gd2Ti2O7, in its magnetically orderered phase below ~ 1 K, displays persistent spin dynamics down to temperatures as low as 20 mK. The characteristics of the…

The intrinsic noncollinear spin patterns in rare-earth pyrochlore are physically interesting, hosting many emergent properties, e.g. spin ice and monopole-type excitation. Recently, the magnetic monopole excitation of spin ice systems was…

材料科学 · 物理学 2015-12-18 Lin Lin , Y. L. Xie , J. -J. Wen , Shuai Dong , Z. B. Yan , J. -M. Liu

The magnetothermodynamics of strongly frustrated classical Heisenberg antiferromagnets on kagome, garnet, and pyrochlore lattices is examined. The field induced adiabatic temperature change (dT/dH)_S is significantly larger for such systems…

强关联电子 · 物理学 2007-05-23 M. E. Zhitomirsky

We have measured the low-temperature specific heat of the geometrically frustrated pyrochlore Heisenberg antiferromagnet Gd2Sn2O7 in zero magnetic field. The specific heat is found to drop exponentially below approximately 350 mK. This…

The magnetic insulator Gd2Sn2O7 is one of many geometrically frustrated magnetic materials known to exhibit a nonzero muon spin polarization relaxation rate, $\lambda(T)$, down to the lowest temperature (T) studied. Such behaviour is…

无序系统与神经网络 · 物理学 2011-04-11 P. A. McClarty , J. N. Cosman , A. G. Del Maestro , M. J. P. Gingras

Despite a Curie-Weiss temperature $\theta_{\rm CW} \sim -14$ K, the Tb2Ti2O7 pyrochlore magnetic material lacks long range magnetic order down to at least $T^*\approx 50$ mK. It has recently been proposed that the low temperature collective…

统计力学 · 物理学 2009-05-07 Hamid R. Molavian , Michel J. P. Gingras

We report the low-temperature magnetothermal properties and spin dynamics of a mixed pyrochlore, Dy2GaSbO7 through the coordination of measurements of dc magnetization, ac susceptibility, and heat capacity, and CF computation. In Dy2GaSbO7,…

材料科学 · 物理学 2021-04-19 Saikat Nandi , Yatramohan Jana , Jahangir Alam , Pallab Bag , S. S. Islam , Ramesh Nath

The pyrochlore insulator Yb2Ti2O7 has attracted the attention of experimentalists and theoreticians alike for about 15 years. Conflicting neutron diffraction data on the possible existence of magnetic Bragg reflections at low temperature…

强关联电子 · 物理学 2016-08-26 A. Yaouanc , P. Dalmas de Reotier , L. Keller , B. Roessli , A. Forget

Electrical resistivity \rho(T) of the 5f ferromagnet UGa2 was investigated for single-crystal samples as a function of pressure and magnetic field. The Curie temperature monotonously increases from T$_{C}$ = 124 K under quasi-hydrostatic…

强关联电子 · 物理学 2015-02-18 A. V. Kolomiets , J. -C. Griveau , J. Prchal , A. V. Andreev , L. Havela

As materials with suppressed ordering temperatures and enhanced ground state entropies, frustrated magnetic oxides are ideal candidates for cryogenic magnetocaloric refrigeration. While previous materials design has focused on tuning the…

The Fermi-Hubbard model describes ultracold fermions in an optical lattice and exhibits antiferromagnetic long-ranged order below the N\'{e}el temperature. However, reaching this temperature in the lab has remained an elusive goal. In other…

量子气体 · 物理学 2018-10-03 Anthony E. Mirasola , Michael L. Wall , Kaden R. A. Hazzard

Muon spin relaxation experiments have been performed in the pyrochlore iridate Pr_2Ir_2O_7 for temperatures in the range 0.025-250 K. Kubo-Toyabe relaxation functions are observed up to > 200 K, indicating static magnetism over this…

强关联电子 · 物理学 2009-11-13 D. E. MacLaughlin , Y. Ohta , Y. Machida , S. Nakatsuji , G. M. Luke , K. Ishida , R. H. Heffner , Lei Shu , O. O. Bernal

The spin dynamics in the geometrically frustrated pyrochlore antiferromagnet $\rm Gd_2Sn_2O_7$ is studied by means of the electron spin resonance. In the ordered phase ($T_N = 1$ K), we have detected three gapped resonance modes. Their…

强关联电子 · 物理学 2013-05-29 S. S. Sosin , L. A. Prozorova , P. Bonville , M. E. Zhitomirsky

We have investigated magnetocaloric effect in double perovskite Gd2NiMnO6 (GNMO) and Gd2CoMnO6 (GCMO) samples by magnetic and heat capacity measurements. Ferromagnetic ordering is observed at ~130 K (~112 K) in GNMO (GCMO), while the Gd…

材料科学 · 物理学 2015-09-30 J. Krishna Murthy , K. Devi Chandrasekhar , Sudipta Mahana , D. Topwal , A. Venimadhav

We report the effect of exchange frustration on the magnetocaloric properties of GdCrTiO$_5$ compound. Due to the highly exchange-frustrated nature of magnetic interaction, in GdCrTiO$_5$, the long-range antiferromagnetic ordering occurs at…

材料科学 · 物理学 2018-09-26 M. Das , S. Roy , N. Khan , P. Mandal

We report systematic low temperature measurements of the DC magnetization, AC susceptibility, and heat capacity of dysprosium pyrogermanate (Dy2Ge2O7) single crystal and powder samples. Our results confirm that Dy2Ge2O7 is an anisotropic…

强关联电子 · 物理学 2009-11-13 X. Ke , M. L. Dahlberg , E. Morosan , J. A. Fleitman , R. J. Cava , P. Schiffer

GdCo$_5$ may be considered as two sublattices - one of Gd and one of Co - whose magnetizations are in antiparallel alignment, forming a ferrimagnet. Substitution of nickel in the cobalt sublattice of GdCo$_5$ has been investigated to gain…

Femtosecond laser induced ultrafast magnetization dynamics have been studied in multisublattice CoxDy1-x alloys. By performing element and time-resolved X-ray spectroscopy, we distinguish the ultrafast quenching of Co3d and Dy4f magnetic…

Highly frustrated antiferromagnets composed of magnetic rare-earth moments are currently attracting much experimental and theoretical interest. Rare-earth ions generally have small exchange interactions and large magnetic moments. This…

统计力学 · 物理学 2009-11-10 Matthew Enjalran , Michel J. P. Gingras