Frequency Dependence of Shot Noise in a Diffusive Mesoscopic Conductor
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چکیده
Detailed measurements of the voltage, temperature, and frequency dependence of the nonequilibrium current fluctuations for a diffusive mesoscopic conductor are reported. The data confirm predictions that a mesoscopic conductor shorter than the electron-electron inelastic length will display shot noise. Furthermore, the low temperatures (100 mK) and high frequencies (1–20 GHz) used for the measurements allow tests in the high-frequency regime (i.e., hn ¿ eV and kT ) of the shot noise, which clearly show the influence of vacuum fluctuations. The quantum noise causes a high-frequency “cutoff” in the shot noise, i.e., the noise is independent of bias voltage for frequencies n . eVyh. [S0031-9007(97)02944-X]
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تاریخ انتشار 1997