Role of coherence in resistance quantization Quantum Hall and quantum point contact versus charge relaxation resistance
نویسندگان
چکیده
The quantization of resistances in the quantum Hall effect and ballistic transport through quantum point contacts is compared with the quantization of the charge relaxation resistance of a coherent mesoscopic capacitor. While the former two require the existence of a perfectly transmitting channel, the charge relaxation resistance remains quantized for arbitrary backscattering. The quantum Hall effect and the quantum point contact require only local phase coherence. In contrast quantization of the charge relaxation resistance requires global phase coherence.
منابع مشابه
“ Charge Relaxation Resistance as a Probe of Many - Body Correlations ” Monday , December 12 , 2011 12 : 00 pm MIT Room 4 - 331
Mesoscopic Circuits witness marked non-local effects in their transport properties because of electron coherence. One important consequence is the quantization of the maximum of the DC conductance in one dimension. Here, we extend the concept of universal quantized resistance to the AC regime and we make a connection with the many-body quantum physics of low-energy models. In particular, we int...
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