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arXiv · 1811.07203

Tunneling density of states, correlation energy, and spin polarization in the fractional quantum Hall regime

Gaurav Chaudhary·Dmitry K. Efimkin·Allan H. MacDonald
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Abstract

We derive exact sum-rules that relate the tunneling density of states (TDOS) of spinful electrons in the fractional quantum Hall (FQH) regime to the spin-dependent many body ground state correlation energy. Because the tunneling process is spin-conserving, the 2D (two-dimensional) to 2D tunneling current $I$ at a given bias voltage $V$ in a spin-polarized system is a sum of majority and minority spin contributions. The sum rules can be used to define spin-dependent gaps that we associate with peaks in 2D to 2D tunneling $I-V$ curves. We discuss different scenarios of tunneling between layers at different fillings in relation to our sum rules. We comment on what recent tunneling experiments say about spin-dependent correlations in light of our sum rules, and propose additional measurements that could provide more specific experimental estimates of spin-dependent correlation energies.

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Gaurav Chaudhary, Dmitry K. Efimkin, Allan H. MacDonald. 2019-08-02. Tunneling density of states, correlation energy, and spin polarization in the fractional quantum Hall regime. https://doi.org/10.1103/physrevb.100.085107

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