Near-complete absorption of intense, ultrashort laser light by sub-lambda gratings.
We demonstrate near-100% light absorption and increased x-ray emission from dense plasmas created on solid surfaces with a periodic sub-lambda structure. The efficacy of the structure-induced surface plasmon resonance, responsible for enhanced absorption, is directly tested at the highest intensities to date (3 x 10{15} W cm{-2}) via systematic, correlated measurements of absorption and x-ray emission. An analytical grating model as well as 2D particle-in-cell simulations conclusively explain our observations. Our study offers a definite, quantitative way forward for optimizing and understanding the absorption process.
Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400005, India.
Subhendu
S
Kahaly
S K
SK
Yadav
W M
WM
Wang
S
S
Sengupta
Z M
ZM
Sheng
A
A
Das
P K
PK
Kaw
G Ravindra
GR
Kumar