• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

2016 Fiscal Year Final Research Report

Observation of elementary excitations in quantum spin ice

Research Project

  • PDF
Project/Area Number 15K13521
Research Category

Grant-in-Aid for Challenging Exploratory Research

Allocation TypeMulti-year Fund
Research Field Condensed matter physics II
Research InstitutionKyoto University

Principal Investigator

Tokiwa Yoshifumi  京都大学, 理学研究科, 特定研究員 (30737458)

Co-Investigator(Renkei-kenkyūsha) MATSUDA Yuji  京都大学, 理学研究科, 教授 (50199816)
NAKATSUJI Satoru  東京大学, 物性研究所, 教授 (70362431)
YASUI Yukio  明治大学, 理工学部, 準教授 (80345850)
UDAGAWA Masafumi  学習院大学, 理学部, 準教授 (80431790)
Research Collaborator YAMASHITA Takuya  
TERAZAWA Daiki  
Project Period (FY) 2015-04-01 – 2017-03-31
Keywords素励起 / スピン液体 / スピンアイス / 熱伝導 / 幾何学的磁気フラストレーション
Outline of Final Research Achievements

Quantum spin liquid is a novel ground state of matter where spins are quantum mechanically fluctuating down to absolute zero temperature. Its nature is manifested itself in exotic properties of elementary excitations, such as spin fractionalization and gauge fluctuations. One of the candidates for quantum spin liquid state is quantum spin ice system, where fluctuations are characterized by the exotic elementary excitations, charged monopoles and photon.
In this project, we have studied spin excitations of the quantum spin ice systems, Yb2Ti2O7 and Pr2Zr2O7, by measuring thermal conductivity. In the former, we found that magnetic monopoles propagate coherently in the crystal lattice due to the influence of quantum fluctuations. In the latter, we have observed anomalous enhancement of thermal conductivity at very low temperature. This may be the first observation of photon, which corresponds to gauge fluctuations in quantum spin liquid.

Free Research Field

実験個体物理

URL: 

Published: 2018-03-22  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi