Observation of hot-electron shot noise in a netallic resistor.

We have measured the current noise of silver thin-film resistors as a function of current and temperature and for resistor lengths of 7000, 100, 30, and 1 mm . As the resistor becomes shorter than the electron-phonon interaction length, the current noise for large current increases from a nearly current independent value to the interacting hot-electron value s p 3y4d2eI . However, further reduction in length below the electron-electron interaction length decreases the noise to a value approaching the independent hot-electron value s1y3d2eI first predicted for mesoscopic resistors. [S0031-9007(96)00179-2]