Cryogen Free Desktop Vibrating Sample Magnetometer (VSM) to 5 Tesla

1. Cryogen Free Desktop Vibrating Sample Magnetometer (VSM) to 5 Tesla

2. Background • Cryogenic Ltd are pioneers of Cryogen Free magnet systems. • Prior to this development high magnetic fields were only available to those with access to liquid helium. • Alternatives such as water cooled electromagnets require very large power units. • The cryogen free technology allows magnets of a wide range of fields and dimensions to be built using the same method of refrigeration.

3. 5 Tesla Desktop Cryogen Free VSM

4. Cryogen Free VSM • The Basic system includes: • The superconducting magnet up to 5 Tesla • The VSM probe. • Cryocooler and compressor. • Electronics Rack housing the bipolar magnet power supply, temperature controller, thermometers, scanner and the measurement option electronics. • The computer (Pentium based with high resolution TFT screen), • including all software, I/O, IEEE and other necessary cards for measurements. • LabVIEW operating software.

5. Desktop Cryogen Free VSM Magnetic field range: up to 5 Tesla Central field homogeneity: 0.1% over samples (0.01% optional) Persistent mode decay rate: 10ppm / hour (optional switch) Field Sweep rate: 0.5T/min Sample temperature range: 1) Room temperature only 2) 77K to 300K 3) up to 1000K with furnace Maximum sample size (in VSM): 8mm diameter VSM vibration amplitude: 0.5, 1, 2mm peak to peak (optically controlled) VSM vibration frequency: 15 to 25 Hz Typical Base noise (with 10 second averaging): 10-6 emu Accuracy and reproducibility: 0.5% Temperature setting period (if applicable): 5 minutes if dT is ~5K Temperature control (if applicable): 100mK @ 100K (with Lakeshore series unit)

6. Model No mini-CFM-3T-51-H3 mini-CFM-5T-51-H3 mini-CFM-5T-51-H3 Magnetic field 2 Tesla Solenoid 3 Tesla Solenoid 5 Tesla solenoid Field direction to bore Axial Axial Axial Homogeneity in 10mm DSV 0.1% 0.1% 0.1% Persistency (optional switch) 1 x 10-5 per hour 1 x 10-5 per hour 1 x 10-5 per hour Room temperature bore 51mm bore 51mm bore 51mm bore Cooldown 300K to operating temperature 14 hours 15 hours 18 hours Ramp time 0 Tesla to full field 5 minutes 6 minutes 10 minutes Operating current <60 Amps <60 Amps 60 Amps Desktop Cryogen Free VSMModel Range

7. The Advantages of • Cryogen Free Facility • Low Operating Costs as liquid helium is not required. • Ease of use as there are no cryogen transfers to make. • Independent and convenient operation • Fast Ramping capability • Automated operation • May be used in any orientation.

8. Automation • The system is installed with the National Instruments LabVIEW operating software and a standard Cryogenic applications package, which allows the complete system to be run under computer control. • This allows:  • Control of magnetic field • Fail-safe shutdown even with power failure. • Better data presentation, real data and then curve fitted data. • Full development software licence allowing the user to develop special applications

9. Optional ExtrasOption 2: High temperature oven insert To perform measurements at above room temperature, an oven insert is offered which increases the standard temperature range. In normal operation, the system has a continuous temperature range of 77K to 300K. With the oven insert this can complemented by a temperature range of 300K to 1000K.

10. Other Applications Of Cryogen free magnets. • Magneto-optical effects, EPR, ESR and NMR • Industrial applications eg; process of industrial minerals including China Clay and Calcium Carbonate. • Synchrotron and Gyrotron magnets to generate X-rays and tuneable microwave. • Medical Applications • Magnetic Resonance Imaging