Resonant tunneling and Kondo effect in a dissipative environment and quantum phase transitions


Chung-Ting Ke

Quantized tunneling of electrons into a quantum dots (QD) due to small capacitance known as Coulomb Blockade has been studied for decades. When a QD is coupled to a weak surrounding (such as highly resistive leads), a dissipative environment for electron tunneling is created. Three mechanisms can be clearly identified in the dissipative environment tunneling: co-tunneling, sequential tunneling, and resonant tunneling. The interaction between electrons and its environment is determined mainly by their coupling strength which can be controlled by the local gate voltage and leads resistance. Additionally, fundamental phenomena such as Kondo Effect, electromagnetic modes, and exotic electron states can be studied. We have recently found an universal bias and temperature scaling for dissipative quantum tunneling of carbon nanotube quantum dots, in which a successful mapping from dissipative system to Luttinger liquid has been proved, and the crossover of phase diagram has been depicted.

Ting received a laser pointer with his talk.

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