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Interference and interaction effects in multi-level quantum dots

Daniel Boese·Walter Hofstetter·Herbert Schoeller
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Abstract

Using renormalization group techniques, we study spectral and transport properties of a spinless interacting quantum dot consisting of two levels coupled to metallic reservoirs. For strong Coulomb repulsion $U$ and an applied Aharonov-Bohm phase $ϕ$, we find a large direct tunnel splitting $|Δ|\sim (Γ/π)|\cos(ϕ/2)|\ln(U/ω_c)$ between the levels of the order of the level broadening $Γ$. As a consequence we discover a many-body resonance in the spectral density that can be measured via the absorption power. Furthermore, for $ϕ=π$, we show that the system can be tuned into an effective Anderson model with spin-dependent tunneling.

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Daniel Boese, Walter Hofstetter, Herbert Schoeller. 2001-10-02. Interference and interaction effects in multi-level quantum dots. https://doi.org/10.1103/physrevb.64.125309

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