Top-loading small-sample calorimeters for measurements as a function of magnetic field angle

In quasi-low-dimensional systems, the existence of a particular physical state and the temperature and magnetic-field-dependence of its phase boundary often strongly depends on magnetic field orientation. To investigate magnetic field orientation dependent phase transitions in these materials, we have developed rotatable miniature and sub-miniature sample-in-vacuum calorimeters that operate in dc magnetic fields up to 18 and 45 tesla. The calorimeters cover the temperature range from below 0.1 K to above 10 K; they are able rotate a full 360 degrees relative to the applied magnetic field while remaining at base temperature. Samples are typically on the order of 1 mg in mass and up to 2 mm² × 0.5 mm in volume