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Register a new userFermi edge singularities in transport through lateral GaAs quantum dots
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Added by
Tobias Stefan Kr\\\"ahenmann
Publication date
2017
fields
Physics
and research's language is
English
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We measure tunnelling currents through electrostatically defined quantum dots in a GaAs/AlGaAs heterostructure connected to two leads. For certain tunnelling barrier configurations and high sample bias we find a pronounced resonance associated with a Fermi edge singularity. This many-body scattering effect appears when the electrochemical potential of the quantum dot is aligned with the Fermi level of the lead less coupled to the dot. By changing the relative tunnelling barrier strength we are able to tune the interaction of the localised electron with the Fermi sea.
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