title: Spin-current probe for phase transition in an insulator.
abstract: Spin fluctuation and transition have always been one of the central topics of magnetism and condensed matter science. Experimentally, the spin fluctuation is found transcribed onto scattering intensity in the neutron-scattering process, which is represented by dynamical magnetic susceptibility and maximized at phase transitions. Importantly, a neutron carries spin without electric charge, and therefore it can bring spin into a sample without being disturbed by electric energy. However, large facilities such as a nuclear reactor are necessary. Here we show that spin pumping, frequently used in nanoscale spintronic devices, provides a desktop microprobe for spin transition; spin current is a flux of spin without an electric charge and its transport reflects spin excitation. We demonstrate detection of antiferromagnetic transition in ultra-thin CoO films via frequency-dependent spin-current transmission measurements, which provides a versatile probe for phase transition in an electric manner in minute devices.
authors: WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.|Spin Quantum Rectification Project, ERATO, Japan Science and Technology Agency, Sendai 980-8577, Japan.
authors: Zhiyong
authors: Z
authors: Qiu
authors: Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA.
authors: Jia
authors: J
authors: Li
authors: WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.|Spin Quantum Rectification Project, ERATO, Japan Science and Technology Agency, Sendai 980-8577, Japan.
authors: Dazhi
authors: D
authors: Hou
authors: Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors: Elke
authors: E
authors: Arenholz
authors: Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors: Alpha T
authors: AT
authors: N'Diaye
authors: Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA.
authors: Ali
authors: A
authors: Tan
authors: Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.|PRESTO, Japan Science and Technology Agency, Saitama 332-0012, Japan.
authors: Ken-Ichi
authors: K
authors: Uchida
authors: WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
authors: Koji
authors: K
authors: Sato
authors: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors: Satoshi
authors: S
authors: Okamoto
authors: Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA.
authors: Yaroslav
authors: Y
authors: Tserkovnyak
authors: Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA.
authors: Z Q
authors: ZQ
authors: Qiu
authors: WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.|Spin Quantum Rectification Project, ERATO, Japan Science and Technology Agency, Sendai 980-8577, Japan.|Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.|Advanced Science Research Center, Japan Atomic Energy Agency, Tokai 319-1195, Japan.
authors: Eiji
authors: E
authors: Saitoh