Quantum Design PPMS
These two commercial cryostats provide computer- controlled experimental platforms which can access temperatures between 1.8 and 400 K and 0.35 and 400K, with maximum magnetic fields of 9 and 14 tesla respectively. Both are equipped with the continuous low-temperature capability which allows continuous data-taking at temperatures below 4.2 K as opposed to "one-shot" operation. These systems are extremely flexible, essentially allowing any measurement which can be fit in a 25-mm diameter area. The crystats have been used for magnetotransport, magneto- capacitance, magnetic susceptibility, heat capacity, and magnetocaloric measurements. Any of these measurements can be performed with minimal set-up time (1 day or less), which allows a great deal of flexibility in conducting experiments. For more information, visit Quantum Design's website.
In addition to the above systems, the laboratory includes a flow cryostat capable of reaching temperatures between 3 K and room temperature. The sample space in this cryostat is in a narrow (1 inch diameter) tail which can be inserted within an electromagnet for rapid field changes. The laboratory also includes a wide range of electronic measurement capabilities including 3 Linear Research LR-700 resistance bridges, highly sensitive capacitance bridges (two manufactured by Andeen-Hagerling and one by General Radio), several lock-in amplifiers and numerous digital multimeters, power supplies, etc.
Quantum Design MPMS
For sensitive magnetic measurements, the laboratory contains two magnetometers, which can access temperatures from 1.8 to 800 K. These are computer-controlled cryostats which can measure the magnetization of samples as a function of both temperature and magnetic field (up to 5.5 and 7 tesla respectively). Both magnetometers are equipped with the RSO option for the highest sensitivity and also with the continuous low-temperature capability which allows continuous data-taking at temperatures below 4.2 K as opposed to "one-shot" operation. For more information, visit Quantum Design.
Dilution Refrigerator System
Oxford Instruments Kelvinox 100
For the lowest temperatures, the Kelvinox 100 is capable of reaching temperatures as low as 0.010 Kelvin and magnetic fields as high as 9 Tesla. This system is equipped as a general purpose cryostat, allowing a wide range of measurements, and it has been used for measurements of electrical and thermal transport properties, magnetic susceptibility, magnetization, and heat capacity. For more information, visit Oxford Instruments on the web.
Magnetic Force Microscopy
Our lab is outfitted with a magnetic force microscope (MFM) system for imaging frustrated arrays of single-domain ferromagnetic islands. The system consists primarily of the Multimode atomic force microscope made by Veeco Instruments which is outfitted with magnetic tips to become an MFM. The head of the system is made with non-magnetic parts so that we can take data in the presence of a strong magnetic field, and the MFM can be operated between the pole faces of a GMW electromagnet in fields of up to 0.3 tesla.