A research group led by Professor Eiji Saitoh (who also serves as Team Director at the RIKEN Center for Emergent Matter Science and Principal Investigator at the Advanced Institute for Materials Research=AIMR, Tohoku University), in collaboration with Junior Principal Mehrdad Elyasi and Principal Investigator Gerrit Ernst-Wilhelm Bauer at the AIMR, Tohoku University, has successfully observed a “thermal squeeze state” in which the thermal fluctuations of collective spin excitations (magnons) in a magnetic material are compressed in a specific direction. In addition to single-mode thermal squeezing, they demonstrated two-mode squeezing, in which correlations arise between two magnon modes that exist asymmetrically on the upper and lower surfaces of a thin film, and showed that this state persists even near room temperature. This “squeezing” of thermal fluctuations in magnetic materials is expected to serve as a new foundational technology for realizing future quantum information technologies, such as the ultimate reduction of noise in magnetic devices and quantum entanglement in magnetic materials, as well as highly efficient information heat engines. The paper reporting these results was published in the online edition of “Nature Physics” on June 1.
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