Condensation of exciton polaritons in a flatband of a deformed triangle lattice at room temperature

J Jing Wei (State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Science and Engineering) X Xiaokun Zhai (Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,) Q Qiang Ai C Chunzi Xing (Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,) X Xinmiao Yang (Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,) Y Yuan Cai (School of Chemical Engineering and Technology, Key Laboratory for Green Chemical Technology of Ministry of Education, Tianjin University) T Tuo Wang X Xianxiong He (College of New Materials and Chemical Engineering, Beijing Institute of Petrochemical Technology 5 , Beijing 102617,) D Dongxue Wang S Sen An (Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,) T Tianyu Liu (International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics) H Haitao Dai L Liefeng Feng (Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,) T Tingge Gao (Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,)

Abstract

Flatbands in the periodic electronic or photonic structures attract intensive attention due to their infinite effective mass, which leads to plenty of physical phenomena, for example, the localization of electrons or photons. However, direct observation of bosonic condensate in the triangle lattice with tunable flatband at room temperature is not realized yet. In this work, we fabricated a microcavity with a triangle lattice potential and perovskite CsPbBr3 as the gain material at room temperature. In this microcavity, polariton bands due to the coupling among the triangle lattice are observed, and exciton polariton condensation is realized. By deforming the triangle lattice such that the coupling between the potential sites is modulated, two exciton polariton flatbands with different energies are observed. Above threshold, exciton polaritons condense at the higher-energy flatband, which experiences larger gain. Our results offer a method to investigate the polariton flatband induced interesting physical phenomenon by engineering a two-dimensional photonic lattice at room temperature.

Article Details

Volume / Issue Vol. 126, Issue 15
Published April 14, 2025
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (14)

J

Jing Wei

State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Science and Engineering

X

Xiaokun Zhai

Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,

Q

Qiang Ai

C

Chunzi Xing

Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,

X

Xinmiao Yang

Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,

Y

Yuan Cai

School of Chemical Engineering and Technology, Key Laboratory for Green Chemical Technology of Ministry of Education, Tianjin University

T

Tuo Wang

X

Xianxiong He

College of New Materials and Chemical Engineering, Beijing Institute of Petrochemical Technology 5 , Beijing 102617,

D

Dongxue Wang

S

Sen An

Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,

T

Tianyu Liu

International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics

H

Haitao Dai

L

Liefeng Feng

Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,

T

Tingge Gao

Department of Physics, School of Science, Tianjin University 1 , Tianjin 300072,