| | |
| | |
Stat |
Members: 3643 Articles: 2'488'730 Articles rated: 2609
29 March 2024 |
|
| | | |
|
Article overview
| |
|
Large enhancement of the thermopower in Na$_x$CoO$_2$ at high Na doping | Minhyea Lee
; Liliana Viciu
; Lu Li
; Yayu Wang
; M. L. Foo
; S. Watauchi
; R. A. Pascal Jr.
; R. J. Cava
; N. P. Ong
; | Date: |
15 Jun 2006 | Subject: | Strongly Correlated Electrons; Materials Science | Abstract: | Research on the oxide perovskites has uncovered electronic properties that are strikingly enhanced compared with those in conventional metals. Examples are the high critical temperatures of the cuprate superconductors and the colossal magnetoresistance in the manganites. The conducting layered cobaltate $
m Na_xCoO_2$ displays several interesting electronic phases as $x$ is varied including water-induced superconductivity and an insulating state that is destroyed by field. Initial measurements showed that, in the as-grown composition, $
m Na_xCoO_2$ displays moderately large thermopower $S$ and conductivity $sigma$. However, the prospects for thermoelectric cooling applications faded when the figure of merit $Z$ was found to be small at this composition (0.6$<x<$0.7). Here we report that, in the poorly-explored high-doping region $x>$0.75, $S$ undergoes an even steeper enhancement. At the critical doping $x_psim$ 0.85, $Z$ (at 80 K) reaches values $sim$40 times larger than in the as-grown crystals. We discuss prospects for low-temperature thermoelectric applications. | Source: | arXiv, cond-mat/0606426 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
|
| |
|
|
|
| News, job offers and information for researchers and scientists:
| |