Superconducting magnet issues "shaken" out of them, until they are eventually able to operate reliably at their full planned current without experiencing quenches. Although the idea of making electromagnets with superconducting wire was proposed by Heike Kamerlingh Onnes shortly after he discovered superconductivity in 1911, a practical superconducting electromagnet had to await the discovery of superconducting materials that could support large critical supercurrent densities in high magnetic fields. The first successful superconducting magnet was built by G.B. Yntema in 1955 using niobium wire and achieved a field of 0.7 T at 4.2 K. Then, in 1961, J.E. Kunzler, E. Buehler, F.S.L. Hsu,
Wander Johannes de Haas de Haas started paralegal studies in 1895. After completion of two of three parts of the examinations and having worked in a lawyer's office for some time, he decided to change career and become a physicist instead. After passing the qualifications exams for admission to University, he started to study physics at the University of Leiden in 1900 under Heike Kamerlingh Onnes and Johannes Petrus Kuenen. He earned his doctorate in 1912, under Kamerlingh Onnes, with a thesis entitled: "Measurements on the Compressibility of Hydrogen." After getting his degree, de Haas worked in Berlin as a researcher at the Physikalische