Professor Shigeki Takeuchi and his colleagues at Kyoto University have demonstrated for the first time a quantum shutter in which two slits in a superposition state are closed simultaneously. In 2003, it was proposed that a quantum shutter with two slits closed in a superposition state would be able to bounce back photons without losing its superposition state, but after 13 years, Professor Takeuchi and his colleagues have succeeded in constructing and demonstrating an optical quantum circuit. The resultant paper was published in Scientific Reports on 14 October.
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