セミナー案内

日時
    
7月11日 (水), 13:30-
場所
京都大学理学部 5号館 413
講演者
Kaoru Mizuta
(Condensed Matter Theory Group)
タイトル
"Spatial-Translation-Induced Discrete Time Crystals"
備考欄 (アブストラクト等)

Abstract:
Time crystals, where time translation symmetry is spontaneously broken, are novel phases of matters in that they are proved to exist only in nonequilibrium[1]. In particular, time crystals in Floquet systems, called discrete time crystals (DTCs), have attracted much interest because of theoretical developments[2,3] and recent experimental realization[4,5].
In many of conventional DTCs, symmetry operation and its symmetry breaking are utilized [2,3], but only on-site symmetries are focused on. Therefore, we propose a new kind of DTCs named "spatial-translation-induced DTC" (STI-DTC), which is realized by spatial translation and its symmetry breaking[6]. By focusing on spatial translation symmetry, STI-DTCs have notable properties which do not exist in conventional time crystals--high controllability of time crystal orders and nontrivially oscillating local transport corresponding to fractional Thouless pumping. We have also proposed a new way to realize DTCs in quantum circuits as an experimental platform.
In the seminar, after providing a brief review of conventional DTCs, I would like to discuss our new DTC, especially its realization, properties, and platforms.


Reference:
[1] H. Watanabe, and M. Oshikawa, Phys. Rev. Lett. 114, 251603 (2015).
[2] D. V. Else, B. Bauer, and C. Nayak, Phys. Rev. Lett. 117, 090402 (2016).
[3] D. V. Else, B. Bauer, and C. Nayak, Phys. Rev. X 7, 011026 (2017).
[4] J. Zhang, P. W. Hess, A. Kyprianidis, et al., Nature 543, 217 (2017).
[5] S. Choi, J. Choi, R. Landig, et al., Nature 543, 221 (2017).
[6] K. Mizuta, K. Takasan, M. Nakagawa, and N. Kawakami, arXiv: 1804.01291.