Low-disorder artificial graphene in nano-patterned triangular antidot lattice of GaAs Heterostructure
ORAL
Abstract
Artificial graphene (AG) in semiconductors have been realized with honeycomb dot lattices [1] on 2D electron systems in GaAs quantum well to serve as advanced quantum simulators for probing novel electron behavior. Small period triangular antidot lattices, where well-defined massless Dirac fermions occur, have not been realized. Here, we report on recent experiments in low-disorder triangular antidot lattice and exploration of collective modes in created electron states by optical spectroscopy experiments using photoluminescence and resonant inelastic light scattering (RILS) at low temperature[2]. Using the cutting-edge fabrication technology, we fabricated small-period triangular antidot lattice (as small as 70 nm), which has an effective honeycomb lattice constant of about 40nm, on GaAs quantum well. In the RILS measurement, the massless Dirac fermions are clearly revealed by the intersubband transition and low energy transitions, well described by modeling the AG band structure. Interplay between quasiparticle interactions and lattice topology will be discussed. [1] S. Wang, et al. accepted in Nature nano. [2] L. Du, et al., in preparation.
*Supported by DOE_BES Award DE-SC0010695.
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Presenters
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Lingjie Du
- Department of Applied Physics and Applied Mathematics, Columbia University