DRY ICE 4K Mossbauer Cryostat
System Type: Dry
Temperature Range: <5K to 300K
Windows: Two mylar windows 180º apart.
Sample Change: <5 minutes without system warm-up
High temperature (500 K, 800 K) options available
The system uses a Gifford-McMahon cold head to cool down a column of static helium exchange gas; the sample probe is inserted into this gas column. This method of cooling allows the sample to be cooled uniformly regardless of shape as its entire surface area is in contact with the exchange gas. Samples can be removed from the system at any point in time regardless of the systems running, this make the system very flexible in operation and has the added benefit short sample change over times. Samples can be changed in as little as five minutes.
In order to minimise the effect of vibrations on Mossbauer spectroscopy the sample probe is suspended from an anti-vibration frame. The probe is connected to the cryostat via a soft bellows which isolate it from the vibration of the cold head. To minimise vibrations from the cryostat to the surrounding equipment it is attached to an independent anti-vibration frame. This configuration offers excellent vibration levels and portability as no permanent fixings are required. The source and detector can be easily attached to the anti-vibration stand via simple bracketry or a shelf.
The ICE Oxford cryostat is an essential piece of equipment in our Mössbauer Spectroscopy laboratory for Earth and Environment (MoSEE) at the University of Stirling. My overarching research interest is in the (bio)geochemical iron cycle and its interaction with the carbon cycle and other nutrient elements. These interactions proceed via reactive iron species which often occur in nanoparticulate form in which they display superparamagnetic behaviour. In order to investigate such particles fully, we need to be able to obtain Mössbauer spectra at different temperatures all the way down to liquid helium temperature (4.2 Kelvin). The bespoke cryostat built by ICEoxford reaches this temperature (and below!) reliably within a couple of hours. It holds all temperatures between liquid helium temperature and room temperature stable. We have not experienced any significant temperature fluctuations or line broadening due to vibrations of the equipment. Overall, I am extremely happy with the value for money this cryostat affords our lab. The company were very receptive to my comments during the design of the instrument and incorporated all of my suggestions, and they have always been responsive to my queries since. We have used the cryostat successfully in a commercial study with a pharmaceutical company. The first scientific paper with results produced using the cryostat is currently in review.
Dr. Christian Schröder