Observation of sub-wavelength phase structure of matter wave with two-dimensional optical lattice by Kapitza-Dirac diffraction

Autor: Zengming Meng, Liangchao Chen, Xiaoling Cui, Jing Zhang, Kai Wen, Lianghui Huang, Liangwei Wang, Pengjun Wang, Lihong Zhou
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Scientific Reports
Scientific Reports, Vol 10, Iss 1, Pp 1-8 (2020)
ISSN: 2045-2322
Popis: We report an experimental demonstration of generation and measurement of sub-wavelength phase structure of a Bose-Einstein condensate (BEC) with two-dimensional optical lattice. This is implemented by applying a short lattice pulse on BEC in the Kapitza-Dirac (or Raman-Nath) regime, which, in the classical picture, corresponds to phase modulation imprinted on matter wave. When the phase modulation is larger than 2π in a lattice cell, the periodicity of phase naturally forms the sub-wavelength phase structure. By converting the phase information into amplitude, we are able to measure the sub-wavelength structure through the momentum distribution of BEC via the time-of-flight absorption image. Beyond the classical treatment, we further demonstrate the importance of quantum fluctuations in the formation of sub-wavelength phase structure by considering different lattice configurations. Our scheme provides a powerful tool for exploring the fine structure of a lattice cell as well as topological defects in matter wave.
Databáze: OpenAIRE