| 摘要 |
A cryostat with a PTR cooling and a boiling fluid medium comprising a two stage sample holder thermalization, especially convenient for AC susceptibility measurement; wherein: - a 1st PTR stage (32) is connected to a recondenser (50) with a thermal link (51) only; the recondenser (50) partially penetrates through the walls (21) of a chamber (20) into a dewar (10) region (11) above a boiling fluid level (12), wherein the recondenser (50) comprises an integrally built thermalization point (52) with the internal thread (53); whereby - a 2nd PTR stage (34) thermally connected to the thermalization block (60), by the use of a non-flexible thermal link (61), wherein said thermal block (60) comprises an another thermalization point (63). The thermalization block (60) enables relative vertical movement of a sample holder with respect to the cryostat without loss of excellent thermal contact with the thermalization point (63). Outside the vacuum chamber (20) there are magnetic coils (80, 81, 82) immersed in the boiling fluid (13), thus achieving substantial reduction of the parasitic effects in measurements. |
