Answers are grounded in this paper and cite their sources.
In this paper we present the results of measurements of the microwave surface impedance of a powder sample and two films of MgB 2 . The powder sample has a T c = 39 K and the films have T c = 29 K and 38 K. These samples show different temperature dependences of the field penetration depth. Over a period of six months, the film with T c = 38 K degraded to a T c of 35 K. We compare the results on all samples with data obtained elsewhere and discuss the implications as far as is possible at this stage.
No takes yet. Share an insight, caveat, or question.
Purnell et al. (2002) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: