Optical probing of correlation driven liquid-to-insulator transition in 2D electron gas

F. Dionigi; F. Rossella; V. Bellani; M. Amado; E. Diez; K. Kowalik; G. Biasiol; L. Sorba

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arXiv · 1007.2936

Optical probing of correlation driven liquid-to-insulator transition in 2D electron gas

F. Dionigi·F. Rossella·V. Bellani·M. Amado·E. Diez·K. Kowalik·G. Biasiol·L. Sorba

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Abstract

We study the quantum Hall liquid and the metal-insulator transition in a high mobility two dimensional electron gas, by means of photoluminescence and magneto-transport. In the integer and fractional regime at nu > 1/3, analyzing the emission energy dispersion we probe the magneto-Coulomb screening and the hidden symmetry of the electron liquid. In the fractional regime above above nu =1/3 the system undergoes the metal-to-insulator transition, and in the insulating phase the dispersion becomes linear with evidence of an increased renormalized mass.

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F. Dionigi, F. Rossella, V. Bellani, M. Amado, E. Diez, K. Kowalik, G. Biasiol, L. Sorba. 2010-07-17. Optical probing of correlation driven liquid-to-insulator transition in 2D electron gas. https://arxiv.org/abs/1007.2936

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