Fluctuation-induced phase in in a transverse magnetic field: theory
Fluctuation-induced phase in in a transverse magnetic field: theory
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横向磁场中的脉动感应相位：理论
DOI：
10.1088/0953-8984/10/28/019
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
T. Nikuni
中科院分区：
文献类型：
--
作者：
A. Jacobs;T. Nikuni
是一个量子三角形反铁磁体，铁磁堆叠，由于Dzyaloshinskiii-Moriya相互作用而具有无公度（IC）结构。由于阻挫引起的经典简并，涨落具有非常大的影响，例如在纵向磁场（垂直于平面，平行于IC波数q）中的相变和在横向磁场（垂直于q）中的q的平台。我们认为涨落也是Werner等人在Neel温度附近的横向场中发现的新IC相的原因（Werner T，Weber H B，Wosnitza J，Kelnberger A，Meschke M，Schotte U，Stuser N，Ding Y and Winkelmann M 1997 Solid State Commun. 102 609）。我们开发和分析相应的最小朗道理论的基态重建由于波动描述唯象，通过一个双二次项。朗道理论给出了两个IC阶段，一个熟悉的从以前的研究;的属性的新的IC阶段，它占据了口袋的温度场相图附近，同意定性与实验发现的新阶段。
is a quantum triangular antiferromagnet, ferromagnetically stacked, with an incommensurate (IC) structure due to a Dzyaloshinskii-Moriya interaction. Because of the classical degeneracy caused by the frustration, fluctuations in have extraordinarily large effects, such as the phase transition in longitudinal magnetic field (normal to the planes, parallel to the IC wavenumber q) and the plateau in q in transverse field (perpendicular to q). We argue that fluctuations are responsible also for the new IC phase discovered in transverse field near the Neel temperature , by Werner et al (Werner T, Weber H B, Wosnitza J, Kelnberger A, Meschke M, Schotte U, Stuser N, Ding Y and Winkelmann M 1997 Solid State Commun. 102 609). We develop and analyse the corresponding minimal Landau theory; the ground-state reconstruction due to fluctuations is described phenomenologically, by means of a biquadratic term. The Landau theory gives two IC phases, one familiar from previous studies; the properties of the new IC phase, which occupies a pocket of the temperature-field phase diagram near , agree qualitatively with those of the new phase found experimentally.