STAGE High frequency Dynamics of the Kondo Effect in Carbon Nanotube

The Kondo effect is a many-body phenomenon arising when a localized quantum degree of freedom is coupled to a Fermi sea of delocalized electrons. This effect can be realized in a carbon nanotube (CNT) quantum dot (QD), which forms an artificial Kondo impurity when it is weakly coupled to source and drain electrodes. Thus a singlet state is formed between the localized state in the CNT and the continuum of the electrodes. A striking consequence is a strong increase of current fluctuations, we have measured in the quantum regime when frequency is larger than temperature (hn>>kBT).
However, we have demonstrated the existence of an unexplained frequency cut-off on the current fluctuations in the Kondo regime, which raises the question of the signature of the internal dynamics of the Kondo effect on current fluctuations.
As we have shown that this cut off is controlled by the symmetry and the coupling strength of the contacts, we plan to develop a new design where this asymetry can be tuned during the measurement.
The goal of the internship is to fabricate multigate CNT QD in order to control the coupling of each contact as well as the Fermi energy in the tube. This should allow a complete understanding of the high frequency dynamics of the Kondo effect. It could also be extended for future experiments with superconducting contacts to control the competition between superconductivity and Kondo effect and even induce a quantum transition in the system.