Post by Lake Shore Cosmin on Apr 9, 2018 9:26:42 GMT -5
Thank you for contacting us!
The data acquisition rate is limited by the time constant which is, in this case, 0.1 s. Therefore the 7400 and 7400S can acquire 10 points per second. The field ramp rate is affected by the size of the electromagnet, electromagnet pole cap size, electromagnet gap and field range. For example, during actual measurement, on a model 7410S, at the 10mm sample access gap, one could ramp the field from -0.5T to 0.5T in one second which results in 1T/s ramp rate. In open loop though, a 10” electromagnet can be brought to >3T in less than a second, but that is not a typical mode of operation.
here you can find other specifications regarding field and electromagnet size and gaps:
Post by Lake Shore Cosmin on Aug 30, 2017 9:19:54 GMT -5
Hello, It’s great to hear that end-users are developing their own software for processing VSM data. On our side, we are doing our best to enable various experimental methods to be performed on our magnetometers. With the acquisition of the Princeton Measurements Corporation in 2012, we expanded our expertise and capabilities to rock magnetism related measurements. I do have examples of files for hysteresis, initial curve and IRM, and I will be happy to provide them to you. To do that, please e-mail me at email@example.com Thank you! Dr. Cosmin Radu Lake Shore Cryotronics
Post by Lake Shore Cosmin on Mar 6, 2017 10:01:38 GMT -5
If the sample or some part of it is ferromagnetic, and if the approximate saturation field is known, we should apply a field equal with the saturation field or larger. Since the field applied during moment gain calibration is 5000 Oe, it became the norm to just use this value to saddle most of the samples. The samples with significant diamagnetic contribution, such as a very thin ferromagnetic film on glass substrate, may benefit from applying a lower field, for example 1000 Oe, in order to avoid the moment being too low. In such special cases, it may be beneficial to only saddle visually, run a quick hysteresis measurement, and only afterwards choose a suitable saddling field. In any case, I recommend trying first to saddle with a 5000 Oe field.