Field controlled current modulators based on tunable barrier strengths

US5705824A · kind A · utility

Assignee

• The United States of America as represented by the Secretary of the Army · US

Inventors

• Gerald J. Lafrate · Raleigh, US
• Jun He · Miaocheng, CN
• Mitra Dutta · Tinton Falls, US
• Michael A. Stroscio · Durham, US

Key dates

• Filing date: Jun 30, 1995
• Grant date: Jan 6, 1998
• Expiry date: Jun 30, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D30/43
• WIPO field: Micro-structural and nano-technology
• WIPO sector: Chemistry

Abstract

A carrier transport media is doped with impurities or includes barrier structures within or on the carrier transport media and a sinusoidally alternating external electric field(s) with frequencies equal to the Bloch frequency divided by an integer is applied to the carrier transport media to alter the effective barriers of the impurities or barrier structures to an arbitrarily large potential compared to the zero field barrier potential. The various impurities or barrier structures are band engineered and deposited, grown or implanted in the carrier transport media and can take any form such as barrier layers in or on the transport media, laterally induced barriers, and impurities or defects in the carrier transport media. The application of time-dependent external fields across a length of nanoscale or mesoscopic structure leads to an effective renominalization of the barrier potential strengths when the frequency of the applied electric field multiplied by an integer is equal to the Bloch frequency. Under these conditions the transmission probability is altered and the current ratio, i.sub.2 /i.sub.1, will be modulated strongly.