Abstract
A system is described which, using an rf-biased SQUID and an adjustable flux transformer, can be applied to low-drift magnetization measurements. With microwaves as bias signal and a modulation frequency of 11 MHz, a slew rate of 2·107 flux quanta/s in closed-loop operation of the SQUID is achieved. This corresponds to a maximum traceable rate of flux change at the flux transformer input of 4·10−3 V, allowing to investigate also specimens with considerable spontaneous magnetization changes (flux jumps).
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References
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