Superconducting aluminum heat switch and plated press-contacts for use at ultralow temperatures.
We have measured the thermal conductivity of a 0.1-mm-thick Al foil in the normal and superconducting state down to 58 mK. At this temperature, our data give a ratio for the conductivities of k(n)/k(s)=1600 T(-2). They show that Al is a better material for a heat switch than the usually used superconductors because of its large k(n) and large Debye temperature (reducing the lattice conductivity k(s)). In addition, we describe the design of a heat switch and an excellent performing demountable press-contact between Al and Cu, both gold plated, as joint to the switch.
Mueller
R M
RM
Institut für Festkörperforschung, Kernforschungsanlage Jülich, Jülich, West Germany.
Buchal
C
C
Oversluizen
T
T
Pobell
F
F
D000535:Aluminum / Q000737:chemistry*; D003080:Cold Temperature; D004553:Electric Conductivity; D004867:Equipment Design; D019544:Equipment Failure Analysis; D011312:Pressure; D013696:Temperature; D013814:Thermal Conductivity; D013817:Thermography / Q000295:instrumentation*
D000535:Aluminum