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Register a new userShot noise suppression in InGaAs/InGaAsP quantum channels
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Added by
Yoshitaka Nishihara
Publication date
2012
fields
Physics
and research's language is
English
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We have measured the shot noise in a quantum point contact (QPC) fabricated by using InGaAs/InGaAsP heterostructure, whose conductance can be electrically tuned by the gate voltages. The reduced shot noise is observed when the QPC conductance equals to N(2e^2/h) (N=4, 5, and 6), which is the direct experimental evidence of the coherent quantized channel formation in the QPC. The deviation of the observed Fano factor from the theory is explained by the electron heating effect generated at the QPC.
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