Case study of an InAs quantum dot memory : Optical storing and deletion of charge

• We have studied self-assembled InAs quantum dots embedded in an InP matrix using photocapacitance and photocurrent spectroscopy. These dots are potentially promising for memories due to the large confinement energy for holes. In this work we have realized simple quantum dot memory by placing the dots in the space–charge region of a Schottky junction. Our measurements reveal that a maximum of about one hole can be stored per dot. We also find that illumination for an extended period deletes the stored charge. We show that these limitations do not reflect the intrinsic properties of the dots, but rather the sample structure in combination with deep traps present in the sample.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Keyword

Electronics

Photocurrent spectroscopy

Quantum dots

Indium compounds

III-V semiconductors

Semiconductor quantum dots

Photocapacitance

Photoconductivity

Self-assembly

Space charge

Schottky barriers

Deep levels

Optical storage

NATURAL SCIENCES

NATURVETENSKAP

Publication and Content Type

ref (subject category)

art (subject category)