Production of magnetic fields in megagauss region and related measuring techniques

Using the "Cnare effect" or the electromagnetic compression of magnetic flux with a metal liner, very high magnetic fields up to 2.8 MG (or 280 T) have been successfully produced in a pulse form with a rise time of several μs. Observation of a motion of the liner and a process of field generation were in good agreement with computer simulation. Measurement of field intensity was performed by integrating a pulse signal induced in a few turn pickup coil and also by observing Faraday rotation for CdS crystal. Direct measurement of magnetization was performed in submegagauss region by integrating a voltage induced in a search coil by means of a cascade integrator, which ensures a high fidelity amplification. In megagauss region, where
B \gg I
, magnetization process was observed by measuring reversible susceptibility by a high-frequency pulse technique. Some magnetooptical observation is also described. Significance of megagauss fields in solid state physics is discussed. A future project aiming the production of 10 MG (or 1000 T) is also discussed.