When water transforms into steam, or magnetized iron changes to demagnetized iron, Katsushi Hashimoto explains to PhysOrg.com, a phase transition is taking place: "Classical phase transitions...often share many fundamental characteristics near the critical point. Quantum phase transitions also show universal critical behaviors, which are affected not only by temperature but also by quantum mechanics."

"The real space observation of rather complex phenomena due to quantum mechanics is the key access to a descriptive understanding" of the world that governs quantum physics, Hashimoto continues. Hashimoto currently belongs to Tohoku University and to JST-ERATO in Sendai, Japan, but while he was at Hamburg University in Germany, he started experiments with Markus Morgenstern in a group led by Roland Wiesendanger. Getting support from theoretical groups at Universities of Warwick and Ryukyu, he and his collaborators finally succeeded in showing quantum Hall transition in "real" space. The results of the experiments are reported in Physical Review Letters: "Quantum Hall Transition in Real Space: From Localized to Extended States."

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