| 摘要 |
<p>Semiconducting material for example p-type Ge, p-type Si and the like, is formed into a thin foil (10), a few atoms thick, preferably by depositing the material on an atomically flat ([110] plane) surface of an insulating semiconductor substrate (12), for example GaAs, ZnSe and the like. The material used for the foil is from a group characterized by re-entrant constant energy level contours and negative effective charge carrier masses. The foil (10) has length and width dimensions much greater than the thickness. An electric bias field is applied across the length of the foil via electrodes (18) tending to shift the charge carrier population into a sector of negative transverse mass. In this manner the resistance across the width of the foil between connectors (14, 15) becomes negative and electric energy is delivered to external circuitry connected at terminals (28, 29) across the width of the foil. The external circuitry comprises a suitable resonant circuit e.g. an R/C circuit. The output can be modulated by means of a radiant energy source (96) driven from source (94) through modulator (92) and modulating source (90). A stacked structure of two or more layers connected in parallel is disclosed for generating larger currents as may be needed for amplifying and oscillating circuits.</p> |
