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arXiv · 1310.0502

Quantum phase transitions into Kondo states in bilayer graphene

Diego Mastrogiuseppe·Arturo Wong·Kevin Ingersent·Sergio Ulloa·Nancy Sandler
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Abstract

We study a magnetic impurity intercalated in bilayer graphene. A representative configuration generates a hybridization function with strong dependence on the conduction-electron energy, including a full gap with one hard and one soft edge. Shifts of the chemical potential via gating or doping drive the system between non-Kondo (free-moment) and Kondo-screened phases, with strong variation of the Kondo scale. Quantum phase transitions near the soft edge are of Kosterlitz-Thouless type, while others are first order. Near the hard edge, a bound-state singlet appears inside the gap; although of single-particle character, its signatures in scanning tunneling spectroscopy are very similar to those arising from a many-body Kondo resonance.

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Diego Mastrogiuseppe, Arturo Wong, Kevin Ingersent, Sergio Ulloa, Nancy Sandler. 2013-10-01. Quantum phase transitions into Kondo states in bilayer graphene. https://doi.org/10.1103/physrevb.89.081101

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