title: Weak lasing in one-dimensional polariton superlattices.
abstract: Bosons with finite lifetime exhibit condensation and lasing when their influx exceeds the lasing threshold determined by the dissipative losses. In general, different one-particle states decay differently, and the bosons are usually assumed to condense in the state with the longest lifetime. Interaction between the bosons partially neglected by such an assumption can smear the lasing threshold into a threshold domain--a stable lasing many-body state exists within certain intervals of the bosonic influxes. This recently described weak lasing regime is formed by the spontaneously symmetry breaking and phase-locking self-organization of bosonic modes, which results in an essentially many-body state with a stable balance between gains and losses. Here we report, to our knowledge, the first observation of the weak lasing phase in a one-dimensional condensate of exciton-polaritons subject to a periodic potential. Real and reciprocal space photoluminescence images demonstrate that the spatial period of the condensate is twice as large as the period of the underlying periodic potential. These experiments are realized at room temperature in a ZnO microwire deposited on a silicon grating. The period doubling takes place at a critical pumping power, whereas at a lower power polariton emission images have the same periodicity as the grating.
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Long
authors: L
authors: Zhang
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Wei
authors: W
authors: Xie
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Jian
authors: J
authors: Wang
authors: Theory of Quantum Coherent Phenomena in Solids, Centre of Nanoheterostructure Physics, Ioffe Physical Technical Institute of the Russian Academy of Sciences, St. Petersburg 194021, Russia; The Metamaterials Laboratory, Information Technologies, Mechanics, and Optics University, St. Petersburg 199034, Russia;
authors: Alexander
authors: A
authors: Poddubny
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Jian
authors: J
authors: Lu
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Yinglei
authors: Y
authors: Wang
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Jie
authors: J
authors: Gu
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Wenhui
authors: W
authors: Liu
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Dan
authors: D
authors: Xu
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China;
authors: Xuechu
authors: X
authors: Shen
authors: Coordinación de Física Teórica, Instituto de Energías Renovables, Universidad Nacional Autónoma de México, Temixco, Morelos 62580, Mexico; zhanghai@fudan.edu.cn ygr@ier.unam.mx bla@phys.columbia.edu.
authors: Yuri G
authors: YG
authors: Rubo
authors: Physics Department, Columbia University, New York, NY 10027; zhanghai@fudan.edu.cn ygr@ier.unam.mx bla@phys.columbia.edu.
authors: Boris L
authors: BL
authors: Altshuler
authors: Spin Optics Laboratory, St. Petersburg State University, St. Petersburg 198504, Russia; and Physics and Astronomy School, University of Southampton, Highfield, Southampton, SO171BJ, United Kingdom.
authors: Alexey V
authors: AV
authors: Kavokin
authors: State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structure (Ministry of Education), Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China; zhanghai@fudan.edu.cn ygr@ier.unam.mx bla@phys.columbia.edu.
authors: Zhanghai
authors: Z
authors: Chen
keywords: condensate; polariton; superlattice; symmetry breaking; weak lasing