Imaging the Incipient Wigner Electron Lattice in a Quantum Wire
Sheng-Chin Ho1*, Heng-Jian Chang1, Chia-Hua Chang1, G.L. Creeth2, M. Pepper2, J.P. Griffith3, I. Farrer4, G.A.C. Jones3, D.A. Rithie3, Tse-Ming Chen1
1Department of Physics, National Cheng Kung University, Tainan, Taiwan
2Department of Electronic and Electrical Engineering, University College London, London, UK
3Cavendish Laboratory, Cambridge university, Cambridge, UK
4Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield, UK
* presenting author:Sheng-Chin Ho,
One-dimensional system abounds with physics especially considering electron-electron interaction. Electrons have been theoretically predicted to form a zigzag Wigner crystal when the electron density in a quantum wire approaches to specific magnitude. SO far such Wigner crystallization can only be inferred from conductance plateaus [1,2,3] and spatially resolved imaging of it remains a challenge. Here we utilize magnetic focusing technique[4] to probe the formation of a Wigner lattice, in which the spatial distribution of electrons in a quantum wire reveals itself in the magnetic focusing spectrum. Evolution from a focusing peak singlet to doublet — in response to a one -dimensional single row transport to Wigner crystallization— is shown when the density is continuously varied. Additionally, the focusing peak doublet is found to develop into a singlet with increasing temperature.

[1] W. K. Hew et al. Phys. Rev. Lett. 102, 056804 (2009).
[2] L. W. Smith et al. Phys. Rev. B 80, 041306 (2009).
[3] V. V. Nat. Phys. 4, 314 (2008).
[4] H. van Houten et al., Phys. Rev. B 39, 8556(1989).

Keywords: quantum transport, GaAs heterostructure, Wigner crystal