Jönsson P E, Mathieu R, Wernsdorfer W, Tkachuk A M, Barbara B
Department of Physics, Uppsala University, Box 530, SE-751 21 Uppsala, Sweden.
Phys Rev Lett. 2007 Jun 22;98(25):256403. doi: 10.1103/PhysRevLett.98.256403. Epub 2007 Jun 21.
The magnetic properties of single crystals of LiHo(x)Y(1-x)F(4) with x = 16.5% and x = 4.5% were recorded down to 35 mK using a micro-SQUID magnetometer. While this system is considered as the archetypal quantum spin glass, the detailed analysis of our magnetization data indicates the absence of a phase transition, not only in a transverse applied magnetic field, but also without field. A zero-Kelvin phase transition is also unlikely, as the magnetization seems to follow a noncritical exponential dependence on the temperature. Our analysis thus unmasks the true, short-ranged nature of the magnetic properties of the LiHo(x)Y(1-x)F(4) system, validating recent theoretical investigations suggesting the lack of phase transition in this system.
使用微超导量子干涉装置磁力计记录了x = 16.5%和x = 4.5%的LiHo(x)Y(1 - x)F(4)单晶的磁性，温度低至35 mK。虽然该系统被认为是典型的量子自旋玻璃，但我们对磁化数据的详细分析表明，不仅在横向施加磁场时，而且在无磁场时，都不存在相变。零开尔文相变也不太可能，因为磁化似乎遵循对温度的非临界指数依赖关系。因此，我们的分析揭示了LiHo(x)Y(1 - x)F(4)系统磁性的真实短程性质，证实了最近表明该系统缺乏相变的理论研究。
