Cryogen-free physical property measurement system (PPMS)

作为几个正在进行的研究项目的一部分，正在进行热电薄膜和纳米颗粒系统中传输的实验研究。这就需要一个无冷冻剂的测量系统来表征物理固态特性。研究的重点是温度和磁场依赖的电和热输运性质以及比热。所需的温度范围为1.8 K至400 K，所需的磁场范围高达9 T。工作组目前没有可用于低温表征Sebeeck系数、热导率和比热的设备。磁阻和霍尔电阻的表征是可能的与现有的设备，但限于高达4T的场范围。有了这个设备，这个磁场范围将决定性地扩展到高达9 T的磁场范围。由于教师没有返回气态氦的选择，采购无冷冻剂（“封闭循环”）设备势在必行。

As part of several ongoing research projects, experimental research on transport in thermoelectric thin films and nanoparticles system is being performed. This requires a cryogen-free measurement system for the characterization of physical solid-state properties. The focus of the investigations is the temperature and magnetic field dependent electrical and thermal transport properties as well as the specific heat. The desired temperature range is from 1.8 K to 400 K, the desired magnetic field range up to 9 T. The working group currently has no device available for the low-temperature characterization of the Sebeeck coefficient, thermal conductivity and specific heat. The characterization of magnetoresistance and Hall resistance are possible with existing devices, but are limited to a field range of up to 4 T. With this device, this field range will be decisively expanded to a magnetic field range of up to 9 T. Due to the fact that the faculty does not have the option of returning gaseous helium, the procurement of a cryogen-free ("closed-cycle") device is imperative.