Triplon current generation in solids

Yao Chen; Masahiro Sato; Yifei Tang; Yuki Shiomi; Koichi Oyanagi; Takatsugu Masuda; Yusuke Nambu; Masaki Fujita; Eiji Saitoh

doi:10.1038/s41467-021-25494-7

Triplon current generation in solids

Nat Commun. 2021 Aug 31;12(1):5199. doi: 10.1038/s41467-021-25494-7.

Authors

Yao Chen¹, Masahiro Sato², Yifei Tang¹, Yuki Shiomi³, Koichi Oyanagi^{1

4}, Takatsugu Masuda⁵, Yusuke Nambu^{1

6

7}, Masaki Fujita¹, Eiji Saitoh^{8

9

10

11

12}

Affiliations

¹ Institute for Materials Research, Tohoku University, Sendai, Japan.
² Department of Physics, Ibaraki University, Mito, Ibaraki, Japan. masahiro.sato.phys@vc.ibaraki.ac.jp.
³ Department of Basic Science, The University of Tokyo, Tokyo, Japan.
⁴ Faculty of Science and Engineering, Iwate University, Morioka, Japan.
⁵ Institute of Solid State Physics, The University of Tokyo, Kashiwa, Chiba, Japan.
⁶ FOREST, Japan Science and Technology Agency, Kawaguchi, Saitama, Japan.
⁷ Organization for Advanced Studies, Tohoku University, Sendai, Japan.
⁸ Institute for Materials Research, Tohoku University, Sendai, Japan. eizi@ap.t.u-tokyo.ac.jp.
⁹ Department of Applied Physics, The University of Tokyo, Tokyo, Japan. eizi@ap.t.u-tokyo.ac.jp.
¹⁰ Institute for AI and Beyond, The University of Tokyo, Tokyo, Japan. eizi@ap.t.u-tokyo.ac.jp.
¹¹ Advanced Institute for Materials Research, Tohoku University, Sendai, Japan. eizi@ap.t.u-tokyo.ac.jp.
¹² Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Japan. eizi@ap.t.u-tokyo.ac.jp.

Abstract

A triplon refers to a fictitious particle that carries angular momentum S=1 corresponding to the elementary excitation in a broad class of quantum dimerized spin systems. Such systems without magnetic order have long been studied as a testing ground for quantum properties of spins. Although triplons have been found to play a central role in thermal and magnetic properties in dimerized magnets with singlet correlation, a spin angular momentum flow carried by triplons, a triplon current, has not been detected yet. Here we report spin Seebeck effects induced by a triplon current: triplon spin Seebeck effect, using a spin-Peierls system CuGeO₃. The result shows that the heating-driven triplon transport induces spin current whose sign is positive, opposite to the spin-wave cases in magnets. The triplon spin Seebeck effect persists far below the spin-Peierls transition temperature, being consistent with a theoretical calculation for triplon spin Seebeck effects.

Publication types

Research Support, Non-U.S. Gov't