Semiconductor Manipulates IR Light

A nanostructure-embedded semiconductor that manipulates light in the IR/terahertz range could benefit applications from imaging to energy efficiency, telecommunications and more.

An artist's rendering of nanoscale metallic wires and metallic particles embedded in semiconductors. Courtesy of Peter Allen, UCSB.

Developed by a team from the University of California, Santa Barbara, the technology uses erbium, a rare-earth metal that has the ability to absorb light in the visible as well as infrared wavelengths.

Pairing it with antimony (Sb), the researchers embedded the resulting compound, erbium antimonide (ErSb), as semimetallic nanostructures within the semiconducting matrix of gallium antimonide (GaSb).

“The nanostructures are coherently embedded without introducing noticeable defects, through the growth process by molecular beam epitaxy,” said Dr. Hong Lu, a researcher in UCSB’s materials and electrical and computer engineering departments, and a lead author of the study. “Secondly, we can control the size, the shape and the orientation of the nanostructures.”

The ErSb/GaSb combination is ideal because of its structural compatibility with surrounding materials, the researchers noted. It allowed them to embed the nanostructures without interrupting the atomic lattice structure of the semiconducting matrix.

Potential functions for the new semiconductor include development of more efficient solar cells, more reliable and higher-resolution biological imaging, medical applications to fight cancer, applications in the new field of plasmonics and the ability to transmit massive amounts of data at higher speeds.

A variety of optics- and electronics-based applications could benefit as well.

The research is published in Nano Letters. (doi: 10.1021/nl402436g)

For more information, visit: www.ucsb.edu