SYSTEM OPTIONS By L. Mauritsen OPT-326 Cryostation Sample In Gas Options Revised August, 2012 The Sample in Gas Module is a powerful tool for the Cryostation which allows cooling of samples by gas conduction or solid thermal conduction. Cooling of the Sample in Gas Module is provided by the Cryostation 4K and 40K stages. The module simply plugs into the sample space of the Cryostation and thermal stages engage automatically. Optical access is provided via four optical ports in the sample area, and positioning of the sample may be manually adjusted by rotating and translating the sample rod. Control of the Cryostation system operations and sample temperature is completely automated, and the gas space is controlled via a specifically designed user interface. The sample space may be evacuated or purged with gas and samples may be changed by flowing helium gas and pulling out the sample rod. Since the Sample in Gas Module can be easily removed, the powerful functionality of the basic Cryostation can still be utilized. The Sample in Gas Module sits on the standard housing. The module includes the 1st and 2nd stage links, which are attached to the sample chamber. The sample rod runs through the Sample in Gas Module and is inserted through the glass insert at the top of the module. There is a port on the Sample in Gas Module that may be connected to a gas or vacuum pump. This allows the user to control the gas content and the pressure of the sample space. Sample in Gas Module 151D Evergreen Drive, Bozeman, MT 59715 / USA TOLL FREE: 877-333-0959 / TEL: 406-551-2796 / [email protected] www.montanainstruments.com OPT-326 Sample in Gas Option Page 1 of 4 V SYSTEM OPTIONS The sample rod can be removed from the Sample in Gas Module. There are several baffles along the length of the sample rod to manage the thermal gradient from the sample space to the top of the rod. The sample can be mounted to the end of the sample rod using VGE or bolts. The sample heater and thermometer run down to the end of the sample rod providing accurate measurement of the sample. The user may rotate the sample rod with the sample attached while cold to change the direction of the sample with respect to the optical access. The sample may also be manipulated vertically. There are 16 electrical feedthroughs at the top of the sample rod and 10 are available for the user. OPT-326 Sample space The Sample in Gas Module uses a unique spring-link technology which allows the module to be installed easily with automatic and reliable coupling of the thermal stages. First Stage Spring Link Second Stage Spring Link Sample Rod When inserting the sample rod, the sample plate on the sample rod will key into a chamfer at the bottom of the gas tube to allow solid conduction cooling of the sample in addition to helium gas cooling. With the sample rod keyed into the solid conduction chamfer there is approximately 29mm diameter by 32.5mm height in the sample chamber. 151D Evergreen Drive, Bozeman, MT 59715 / USA TOLL FREE: 877-333-0959 / TEL: 406-551-2796 / [email protected] OPT-326 Sample in Gas Option Page 2 of 4 V SYSTEM OPTIONS OPT-326 Actual Results: Temperature (K) Sample in Gas Temperatures 6 5 Sample 4 Platform 3 Stage 2 2 Time (each tic is one minute) Cool down before insertion Temperature stabilized Experiments with helium Sample rod fully inserted 10 Temperature during Helium Introduction 9 Temperature (K) 8 7 Sample 6 Platform 5 Stage 2 4 3 2 0 10 20 30 40 Time (min) Sample at 3.7K Helium introduced, temperature rises as gas heats chamber, then cools back down Helium flow turned on, temperature rises as gas heats chamber, then cools until helium liquefies Vacuum pump turned on, sample cools to 3.1K System warms up 151D Evergreen Drive, Bozeman, MT 59715 / USA TOLL FREE: 877-333-0959 / TEL: 406-551-2796 / [email protected] OPT-326 Sample in Gas Option Page 3 of 4 V SYSTEM OPTIONS OPT-326 Sample in Gas System Cool Down Profile: Note that the temperature stability is much less than 10mK. 151D Evergreen Drive, Bozeman, MT 59715 / USA TOLL FREE: 877-333-0959 / TEL: 406-551-2796 / [email protected] OPT-326 Sample in Gas Option Page 4 of 4