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Title: A Noble‐Transition Alloy Excels at Hot‐Carrier Generation in the Near Infrared
Abstract

Above‐equilibrium “hot”‐carrier generation in metals is a promising route to convert photons into electrical charge for efficient near‐infrared optoelectronics. However, metals that offer both hot‐carrier generation in the near‐infrared and sufficient carrier lifetimes remain elusive. Alloys can offer emergent properties and new design strategies compared to pure metals. Here, it is shown that a noble‐transition alloy, AuxPd1−x, outperforms its constituent metals concerning generation and lifetime of hot carriers when excited in the near‐infrared. At optical fiber wavelengths (e.g., 1550 nm), Au50Pd50provides a 20‐fold increase in the number of ≈0.8 eV hot holes, compared to Au, and a threefold increase in the carrier lifetime, compared to Pd. The discovery that noble‐transition alloys can excel at hot‐carrier generation reveals a new material platform for near‐infrared optoelectronic devices.

 
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Award ID(s):
1708991 1507988
NSF-PAR ID:
10458049
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
32
Issue:
23
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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