论文标题
在GAV4S8 Mott绝缘子的压力下的结构，磁性和绝缘体到金属过渡：高达14.7 GPA的丰富相图
Structural, magnetic and insulator-to-metal transitions under pressure in the GaV4S8 Mott insulator: A rich phase diagram up to 14.7 GPa
论文作者
论文摘要
除了其对应用的有希望的潜力外，GAV4S8还显示了具有温度和磁场的非常有趣的物理特性。可以通过施加静水压力来调整这些特性，以揭示和理解这些材料的物理。压力不仅引起GAV4S8中的绝缘体到金属的转变，而且对结构和磁过渡也有有趣的影响。使用压力下的交流量热法，电容和电阻率测量的组合，我们确定了用压力的结构和磁过渡的演变，从而确定了GAV4S8的T-P相图。为了检测绝缘体到金属的过渡，我们使用光导率和直流电阻率测量值，并遵循压力下莫特隙的演变。结构过渡温度随压力而增加，第二个过渡出现在6 GPA以上，表明可能具有很小间隙的新阶段。令人惊讶的是，对铁磁过渡的影响非常弱，该过渡仍然非常接近于在14 GPA左右发生的IMT，这意味着金属状态也可能是磁性的。
In addition to its promising potential for applications, GaV4S8 shows very interesting physical properties with temperature and magnetic field. These properties can be tuned by applying hydrostatic pressure in order to reveal and understand the physics of these materials. Not only pressure induces an insulator-to-metal transition in GaV4S8 but it also has an interesting effect on the structural and magnetic transitions. Using a combination of AC calorimetry, capacitance, and resistivity measurements under pressure, we determine the evolution of the structural and magnetic transitions with pressure and thus establish the T-P phase diagram of GaV4S8. To detect the insulator-to-metal transition, we use optical conductivity and DC resistivity measurements and we follow the evolution of the Mott gap under pressure. The structural transition temperature increases with pressure and a second transition appears above 6 GPa indicating a possible new phase with a very small gap. Pressure has surprisingly a very weak effect on the ferromagnetic transition that persists even very close to the IMT that occurs at around 14 GPa, implying that the metallic state may also be magnetic.
