University of Cambridge > Talks.cam > AMOP list > Hubbard-Mott physics of electrons in an artificial semiconductor lattice

Hubbard-Mott physics of electrons in an artificial semiconductor lattice

Add to your list(s) Download to your calendar using vCal

If you have a question about this talk, please contact pjh65.

In this talk I’ll discuss recent optical and transport results obtained in a high-mobility two-dimensional electron gas confined in a GaAs quantum well and subjected to a lateral potential with honeycomb topology [1,2,3]. By tuning the properties of the honeycomb lattice with a gate voltage and a magnetic field we were able to drive the system into localized or delocalized transport regimes. In this latter case we probed the cyclotron spectrum by means of inelastic light scattering and we identified a novel low-lying excitation at high magnetic fields with unexpectedly large oscillator strength. I will argue in the talk that this new gapped mode is a direct manifestation of the modification of the excitation spectra predicted by the Hubbard model [4]. Since the Hubbard model underpins the essential physics of Mott insulators, our approach offers new venues for experimental simulation of quantum phenomena in a controllable solid-state systems.

  • work done in collaboration with A. Singha, M. Gibertini, M. Polini, B. Karmakar, G. De Simoni, A. Pinczuk, G. Vignale, L.N. Pfeiffer, K.W. West

[1] M. Gibertini et al. Phys. Rev. B RC 79 , 241406 (2009)

[2] G. De Simoni et al. arXiv:1007.3168

[3] A. Singha et al. in preparation

[4] J. Hubbard. Proc. R. Soc. Lond. A 281 , 401 (1964)

This talk is part of the AMOP list series.

Tell a friend about this talk:

This talk is included in these lists:

Note that ex-directory lists are not shown.

 

© 2006-2022 Talks.cam, University of Cambridge. Contact Us | Help and Documentation | Privacy and Publicity