Research

　Quantum entanglement lies at the heart of quantum mechanics and serves as the origin of many remarkable quantum phenomena, including heavy-fermion behavior, the Kondo effect, quantum spin liquids, and quantum phase transitions. A central challenge in modern condensed matter physics is not only to observe such quantum correlations in materials, but also to design and control them.

Our research is based on unique quantum magnets composed of organic radical molecules and metal ions. To engineer quantum states, we have developed a crystal-design strategy termed RaX-D (Radical-based crystal eXpansion-Design), which enables systematic control of the strength, anisotropy, and dimensionality of spin interactions through crystal-space engineering.

Using these materials, we have demonstrated a wide variety of emergent quantum phenomena, including novel spontaneous symmetry breaking and topological quantum phases. Our goal is to uncover universal principles governing quantum matter and to establish an experimental platform for realizing and testing theoretical quantum models in real materials—an approach we refer to as the implementation science of quantum models.

A distinctive feature of our  RaX-D is the seamless integration of all stages of research: molecular design and synthesis, precision measurements under extreme conditions, quantum-chemical calculations, and theoretical analyses. By continuously cycling through the creation, observation, understanding, and redesign of quantum states, we develop quantum materials from the molecular level upward. Through this interdisciplinary, bottom-up approach bridging chemistry and physics, we aim to create new functionalities in quantum magnetism and explore uncharted frontiers of quantum condensed matter science.