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Low and High Temperatures

10 K - 300 K APD / ARS DE202 G

The ARS DE202G is a closed cycle cryostat which uses high pressure helium gas to produce cooling down to 10 K. A helium compressor provides high pressure gas to the cryocooler through a flexible gas line. The expansion of the gas at different stages produces the refrigeration. Low pressure gas is then returned through another gas line where it is recycled through the compressor. This closed loop cycle can be continuously repeated and maintained as needed to produce the desired refrigeration. The DE202G cryostats on XMaS is designed to mount directly onto the phi circle of the Huber diffractometer and can be oriented in any direction at base temperature. Currently there are two of these cryostats on the beamline, one with silicon diode temperature sensors and the second has a cernox sensor installed for use in magnetic fields.

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Both the vacuum shroud (380 µm thick wall) and radiation shield (279 µm thick wall) are equipped with beryllium domes for x-ray studies allowing full access to the sample. The shroud is constructed from non-magnetic stainless steel which slips over a double o-ring on the refrigerator for easy sample change. The radiation shield is constructed from nickel plated copper for effective heat transfer. The distance from the tip APD cryostat ''cold finger'' to the centre of rotation is 17.5 mm. Samples are usually mounted onto a 6 mm diameter copper stub, that can then be mounted into a standard sample holder. For larger or unusually shaped samples, mounts can be made on request. Please contact the beamline staff to discuss your requirements before arriving for the experiment.

10 K - 600 K ARS DE202G Cryofurnace

This cryofurnace is based on the ARS DE202G. The 600 K interface mounts on the cooler and contains an internal mechanical thermal switch which protects the cold end from excessive heat while experiments are carried out at elevated temperatures. A RhFe sensor reads the temperature at the sample position between 16 K and 600 K. A silicon diode sensor mounted on the other side of the thermal switch reads temperatures down to 10 K.

1.7 K - 300 K He 4 ILL Joule Thomson Cryostat

In addition to a commercial standard 2-stage displex cryostat, which operates down to ~10 K and mounts on the phi circle of the diffractometer, a specially adapted 3-stage displex capable of sample temperatures down to 1.7 K is in routine use. This novel device, which has been developed by the cryogenics laboratory at the Institut Laue Langevin, Grenoble, may be operated over a wide range of angles without degradation of base temperature. The 3-stage device is ~40 mm longer than a standard displex, but is installed into the same motorised phi circle mount as all of the other cryostats.

Both the vacuum shroud (500 µm thick wall) and radiation shield (300 µm thick wall) are equipped with beryllium domes.

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1 K - 300 K He 3 ILL Joule Thomson Cryostat

Using the above Joule Thomson cryostat with 3He gas, instead of 4He, test experiments have been made with sample temperatures of 1 K.

Temperature Controllers

The standard temperature controller used on the beamline is the Lakeshore model 340. This controller supports a very wide range of temperature sensors and has four inputs. Further details of this controller can be found on the Lakeshore website.

Furnaces and temperature controllers (on request only!!)

A series of furnaces from the ESRF Sample Environment pool Eurotherm controllers linked to Delta Elektronika power supply SM120-50 or SM120-25 can also be used (on request only!!). The Eurotherm controller is integrated in SPEC and PID parameters, ramp rates, etc. can be changed remotely. Please, contact us for further details.