Acoustoelectric amplification in resonant piezoelectric-semiconductor cavities

An apparatus for acoustoelectric amplification, the apparatus comprising:

• a semiconductor layer;
• at least two access pads communicatively coupled to the semiconductor layer, the at least two access pads being positioned at opposite ends of the apparatus, wherein the at least two access pads are configured to provide an asymmetric drift current profile across a defined acoustic wave propagation path of the semiconductor layer, ensuring a controlled variation in carrier properties;
• a structured electrode arrangement configured to modulate carrier drift velocity relative to the acoustic wave propagation direction;
• wherein at least one of the at least two access pads is positioned in a manner to receive a voltage, current, or both to change a charge carrier property in at least one portion of the semiconductor layer, whereby the positioning of at least one of the at least two access pads causes an electron drift within the charge injection region to be asymmetrical, producing a non-reciprocal signal amplification effect.

A method for producing an apparatus for acoustoelectric amplification, the method comprising:

• providing a semiconductor layer;
• disposing a thin piezoelectric layer onto the semiconductor layer, thereby forming an acoustic heterostructure;
• communicatively coupling at least two radio frequency (RF) signal access ports (RF1 and RF2) to the thin piezoelectric layer, wherein at least one of the at least two RF signal access ports allow for forming a lateral field excitation (LFE) electrode arrangement, wherein the LFE electrode arrangement enhances acoustoelectric interactions between charge carriers and propagating acoustic waves;
• and
• communicatively coupling at least two DC signal access ports (DC1 and DC2) to the semiconductor layer, wherein at least one of the at least two DC signal access ports allow an externally applied DC current to induce electron drift within the charge carrier injection region;
• and
• configuring the semiconductor layer such that the acoustoelectric interactions enable a non-reciprocal gain mechanism dependent on the relative direction of electron drift and acoustic wave propagation.