Atomic-scale observation of localized phonons at FeSe/SrTiO3 interface

Shi，Ruochen1,2; Li，Qize1,2,3; Xu，Xiaofeng4,5; Han，Bo1,2; Zhu，Ruixue1,2; Liu，Fachen2,6; Qi，Ruishi3; Zhang，Xiaowen1,2; Du，Jinlong2; Chen，Ji7,8,9; Yu，Dapeng2,10,11; Zhu，Xuetao4,5; Guo，Jiandong4,5; Gao，Peng1,2,8,9,11

2024-12-01

10.1038/s41467-024-47688-5

Nature Communications   影响因子和分区

2041-1723

In single unit-cell FeSe grown on SrTiO, the superconductivity transition temperature features a significant enhancement. Local phonon modes at the interface associated with electron-phonon coupling may play an important role in the interface-induced enhancement. However, such phonon modes have eluded direct experimental observations. The complicated atomic structure of the interface brings challenges to obtain the accurate structure-phonon relation knowledge. Here, we achieve direct characterizations of atomic structure and phonon modes at the FeSe/SrTiO interface with atomically resolved imaging and electron energy loss spectroscopy in an electron microscope. We find several phonon modes highly localized (~1.3 nm) at the unique double layer Ti-O terminated interface, one of which (~ 83 meV) engages in strong interactions with the electrons in FeSe based on ab initio calculations. This finding of the localized interfacial phonon associated with strong electron-phonon coupling provides new insights into understanding the origin of superconductivity enhancement at the FeSe/SrTiO interface.

SCI

英语

其他

2-s2.0-85191079146

Scopus

1.International Center for Quantum Materials,School of Physics,Peking University,Beijing,100871,China
2.Electron Microscopy Laboratory,School of Physics,Peking University,Beijing,100871,China
3.Department of Physics,University of California at Berkeley,Berkeley,94720,United States
4.Beijing National Laboratory for Condensed Matter Physics and Institute of Physics,Chinese Academy of Sciences,Beijing,100190,China
5.School of Physical Sciences,University of Chinese Academy of Sciences,Beijing,100049,China
6.Academy for Advanced Interdisciplinary Studies,Peking University,Beijing,100871,China
7.Institute of Condensed Matter and Material Physics,Frontiers Science Center for Nano-optoelectronics,School of Physics,Peking University,Beijing,100871,China
8.Collaborative Innovation Center of Quantum Matter,Beijing,100871,China
9.Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials,Peking University,Beijing,100871,China
10.Shenzhen Institute for Quantum Science and Engineering (SIQSE),Southern University of Science and Technology,Shenzhen,518055,China
11.Hefei National Laboratory,Hefei,230088,China

Shi，Ruochen,Li，Qize,Xu，Xiaofeng,et al. Atomic-scale observation of localized phonons at FeSe/SrTiO3 interface[J]. Nature Communications,2024,15(1).

Shi，Ruochen.,Li，Qize.,Xu，Xiaofeng.,Han，Bo.,Zhu，Ruixue.,...&Gao，Peng.(2024).Atomic-scale observation of localized phonons at FeSe/SrTiO3 interface.Nature Communications,15(1).

Shi，Ruochen,et al."Atomic-scale observation of localized phonons at FeSe/SrTiO3 interface".Nature Communications 15.1(2024).