"Photodetection with active optical antennas"

Paper art: gold nanoantennas deposited in SiO2 windows,
coated with ITO, and illuminated with an IR laser

As frequent visitors to this blog may have noticed, the title - "Physics... and other trivial pursuits" - has been a bit deceptive.  I've written a fair amount about my trivial pursuits, but very little indeed about physics. That bias toward non-scientific endeavors has primarily resulted from the embargo placed on my research as we moved toward publication over the past year. 

Yesterday, that embargo was lifted when my paper came out in Science.

The work, conducted at Rice University in conjunction with Heidar Sobhani, Peter Nordlander, and Naomi Halas, is an experimental demonstration of how the 'hot' electrons generated by plasmonic decay can be captured as a photocurrent.

Given the generality of the approach, and the potential for applications in miniature detectors and solar power generation, the paper garnered a fair amount of media attention in the first 24 hours. These writeups do a very nice job of making the science accessible. 

Seeing the beautiful perspective article in Science by Martin Moskovits was particularly exciting. I've had the pleasure of meeting Martin twice this past year - first at the Plasmonics GRS/GRC last summer, and then more recently over a physics luncheon at Rice. The clarity of thought he brings to both life and science is refreshing.

If you're interested in learning a bit more about hot electrons, I've included a few links to articles mentioning my new paper below. Most, although not all, of these articles are based on the Rice University press release written by Jade Boyd.

The Moskovits Perspective:

• Science - "Hot Electrons Cross Boundaries" by Martin Moskovits (May 5, 2011)

Figure 1 (from the Moskovits perspective): "(A) Light excites surface plasmons (depicted as regions of positive and negative charge, top and bottom) that can decay into charge carriers, electrons e− and holes h+. Plasmons in shorter nanorods are excited at shorter wavelengths. The nanorods were grown on a titanium (Ti) buffer layer, 1 nanometer thick, on n-type silicon. (B) An energy diagram showing how excited electrons created by plasmon decay encounter a Schottky barrier at the metal-silicon interface, which share a common Fermi energy EF. Highly energetic electrons are either directly injected into the conduction band of silicon above its band edge, EC, or tunnel through the barrier. The barrier is less than the band gap energy (the difference between EC and valence band edge, EV). Holes and electrons produce a measurable photocurrent collected at the indium tin oxide and indium electrodes. CREDIT: P. HUEY/SCIENCE"

Popular press writups:

• ScienceDaily - "Measurement of 'Hot' Electrons Could Have Solar Energy Payoff; Nanoantennas Hold Promise for Infrared Photovoltaics" (May 6, 2011)
• Physics World - "Nano-antenna fashions charge from light" by Belle Dumé (May 5, 2011)
• Chemistry World (RSC) - "Tuning into solar power with nanoantennas" by Mike Brown (May 5, 2011)
• Rice Media - "Measurement of 'hot' electrons could have solar energy payoff" by Jade Boyd (May 6, 2011)
• PhysOrg - "Measurement of 'hot' electrons could have solar energy payoff" (May 5, 2011)
• Solar Novus Today - "Nanoantennas Hold Promise for Infrared Photovoltaics" by Nancy Lamontagne (May 6, 2011)
• Penn Energy - "Nano-antenna optics + semiconductor electronics = IR photovoltaics" (May 5, 2011)

Blog posts:

• Houston Chronicle : SciGuy - "New technology could capture solar energy now wasted" by  Eric Berger (May 5, 2011)
• Nanoscale views - "Nano for solar" by Doug Natelson (May 5, 2011)
  (my work is just a side note to Doug's excellent overview of various nanotech approaches to enhanced solar power generation)
• Nano Patents and Innovation - "Nanoantennas: Measurement Of 'Hot' Electrons Could Have Solar Energy Payoff" (May 6, 2011)