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Bulk Tunneling at Integer Quantum Hall Transitions

Ziqiang Wang·Shanhui Xiong
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Abstract

The tunneling into the {\em bulk} of a 2D electron system (2DES) in strong magnetic field is studied near the integer quantum Hall transitions. We present a nonperturbative calculation of the tunneling density of states (TDOS) for both Coulomb and short-ranged electron-electron interactions. In the case of Coulomb interaction, the TDOS exhibits a 2D quantum Coulomb gap behavior, $ν(\ve)=C_Q\ave/e^4$, with $C_Q$ a nonuniversal coefficient of quantum mechanical origin. For short-ranged interactions, we find that the TDOS at low bias follows $ν(\ve)/ν(0)=1+(\ave/\ve_0)^γ$, where $γ$ is a universal exponent determined by the scaling dimension of short-ranged interactions.

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Ziqiang Wang, Shanhui Xiong. 1999-07-08. Bulk Tunneling at Integer Quantum Hall Transitions. https://doi.org/10.1103/physrevlett.83.828

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