Measurements of fundamental physical constants h/e/sup 2/ and h/2e at 300 K at THz frequencies

Summary form only given. Recent technological advances in detectors, coupling structures, local oscillators (LO) have made it possible to develop low noise heterodyne receivers for frequencies up to 5 THz. When using Schottky diodes with contact diameters below 1 μm and capacitances as low as 0.25 fF the optimum mixing performance demonstrates ballistic electron transport phenomena at room temperature. The mixing current is given by I/sub opt/=N/sub e/eν and the optimum depletion thickness for all different diodes is given by D/sup 2//sub depl/=(h/2e)μ. The voltage across the device as a function of the normalized optimum current for all measurements results in a resistance very close to h/e/sup 2/.