Abstract
Doping wide-gap materials p type is highly desirable but often difficult. This makes the recent discovery of p-type delafossite oxides, , very attractive. The also show unique and unexplained physical properties: Increasing band gap from , to In, not seen in conventional semiconductors. The largest gap can be mysteriously doped both n and p type but not the smaller gaps and . Here, we show that both properties are results of a large disparity between the fundamental gap and the apparent optical gap, a finding that could lead to a breakthrough in the study of bipolarly dopable wide-gap semiconductor oxides.
- Received 25 September 2001
DOI:https://doi.org/10.1103/PhysRevLett.88.066405
©2002 American Physical Society