Cryogenics SQUID

Cryogenics S700X (Recondensing) SQUID

Specification

• Longitudinal and transverse magnetization can be measured
• Temperature range : 1.6 < T < 320 K
• Field range : 0 < B < 7 T

Operation :

• Rate of temperature change can be controlled using the needle valve.If not changing temperature, needle valve should be opened to the extent that the power shown in the temperature control window is about 10-20% of max value.
• For DC measurements use "Edit Sequence" to write a sequence which can be run using "Start Data Acquisition".
• Sample tube temperature must be set to 5K with the film burner ON.
• After every restart of software, need to initalise the stepper motor.

Maintenance :

• Loud periodic noise from the compressor must never stop.
• If the He level starts to decrease, unblock ice from the He inlet. Safe value of He level >300mm

Troubleshooting :

• SQUID drifting : If drift seen in range 3/4, check if the AC cable is connected. If it is, disconnect it. Other options are to carefully reconnect the cable from the pre-amplifier and to try clearing ice from the He inlet if there is any.
• Measurement frozen : restart the VIs. First try to STOP all VIs and then close them. Restart Sx_main.vi

References :

1. S700X manual by Cryogenics
2. S700X Guidance document
3. S700X Troubleshooting document
4. The manual of S700X : https://wiki.epfl.ch/lqm/documents/S700X_manual_new.pdf
5. Small instrucitons on how to use AC : https://wiki.epfl.ch/lqm/documents/S700X_quick_guide.pdf