東京大学 · Physics and Astronomy
요시노리 토쿠라 교수의 연구실은 강한 전자 간 tương호작용과 스핀-전자 상호작용을 중심으로 한 양자물리현상의 기초 연구를 수행합니다. 특히 코발트 망간산화물의 거대적 자기저항 효과, 다중형성체에서의 자기전기 효과, 스카이미온의 위상적 안정성 등 스핀트로닉스와 나노스케일 소자 응용에 기여할 수 있는 새로운 물질적 현상과 메커니즘을 탐구하고 있습니다. 연구는 주로 자기적, 전기적, 결정학적 자유도의 상호작용을 중심으로 하여, 비보존적 비대칭 시스템에서의 비상호작용 전류 및 스핀 전류의 비대칭 전파를 포함한 비대칭 전자현상에도 확장되고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
The features and mechanism of Colossal Magnetoresistance, or CMR, in manganese oxides as well as device physics are highlighted in this book, with a focus on tunneling MR for some artificial structures. Underlying new science, such as tunable electron-lattice interaction in a metal and roles of orbital degrees of freedom in producing an unconventio
Multiferroics, compounds with both magnetic and ferroelectric orders, are believed to be a key material system to achieve cross-control between magnetism and electricity in a solid with minute energy dissipation. Such a colossal magnetoelectric (ME) effect has been an issue of keen interest for a long time in condensed matter physics as well as a most desired function in the emerging spin-related electronics. Here we begin with the basic mechanisms to realize multiferroicity or spin-driven ferro
Giant magnetotransport phenomena including the field-induced nonmetal-metal transition have been found in single crystals of La 1- x Sr x MnO 3 near the critical composition ( x ≈0.17) for the nonmetal-metal transition and in the temperature region around the magnetic phase transition. Change of the resistivity shows a universal curve as a function of the magnitude of temperature- or field-induced magnetization, the most of which agrees with the prediction by the D =∞ and S =∞ Kondo lattice mode
Skyrmion, a concept originally proposed in particle physics half a century ago, can now find the most fertile field for its applicability, that is, the magnetic skyrmion realized in helimagnetic materials. The spin swirling vortex-like texture of the magnetic skyrmion can define the particle nature by topology; that is, all the constituent spin moments within the two-dimensional sheet wrap the sphere just one time. Such a topological nature of the magnetic skyrmion can lead to extraordinary meta
Cross correlation between magnetism and electricity in a solid can host magnetoelectric effects, such as magnetic (electric) induction of polarization (magnetization). A key to attain the gigantic magnetoelectric response is to find the efficient magnetism-electricity coupling mechanisms. Among those, recently the emergence of spontaneous (ferroelectric) polarization in the insulating helimagnet or spiral-spin structure was unraveled, as mediated by the spin-exchange and spin-orbit interactions.
Directional transport and propagation of quantum particle and current, such as electron, photon, spin, and phonon, are known to occur in the materials system with broken inversion symmetry, as exemplified by the diode in semiconductor p-n junction and the natural optical activity in chiral materials. Such a nonreciprocal response in the quantum materials of noncentrosymmetry occurs ubiquitously when the time-reversal symmetry is further broken by applying a magnetic field or with spontaneous mag
The term “electromagnetism” comes from the fact that the electric and magnetic fields are generally not independent of one another. A changing magnetic field produces an electric field (electromagnetic induction), whereas the motion of electric charges, or electric current, generates a magnetic field (the Biot-Savart law). Typically, electromagnets are wire coils or loops, which tend to be bulky and difficult to fabricate. Would it be possible to devise an electromagnet made from a nano- or micr
