The Tosca Duplex ‘s main design features are shown here; the design enables a complete disassembly to occur so individual components can be replaced or maintained. The system utilises a double indium joint that seals the inner vacuum chamber in turn to the copper cold ring, cold tube and the stainless steel sample volume tube. The copper cold ring has a 4mm fast cooling helium tube, which is the only component that is hard soldered, all other joint are copper eutectic welded where possible and bolted only where necessary. The completed system cool down and sample change data is shown below. The cryostat now reaches a base temperature of 4.5K from start up in 7 hours and will cool a sample down to 20K in 45 minutes; If required the sample can be cooled down using liquid helium through the 4mm helium tube in this case 4.5K is reached in 10minutes and removal of the remaining cold gas will give a single shot of 1K for approximately 3 hours. Maintenance of the 3rd  head and reduced electricity consumption saves significant cost, the base temperature of 4.5K has opened new realms of low temperature study on the Tosca Instrument. 

For information about the Tosca sample changer please click here.