Two-dimensional Mott-Hubbard electrons in an artificial honeycomb lattice.
نویسندگان
چکیده
Artificial crystal lattices can be used to tune repulsive Coulomb interactions between electrons. We trapped electrons, confined as a two-dimensional gas in a gallium arsenide quantum well, in a nanofabricated lattice with honeycomb geometry. We probed the excitation spectrum in a magnetic field, identifying collective modes that emerged from the Coulomb interaction in the artificial lattice, as predicted by the Mott-Hubbard model. These observations allow us to determine the Hubbard gap and suggest the existence of a Coulomb-driven ground state.
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ورودعنوان ژورنال:
- Science
دوره 332 6034 شماره
صفحات -
تاریخ انتشار 2011