February 19, 2015 - Steven Byrnes

The Shockley-Queisser Limit and Its Discontents

In 1961, Shockley and Queisser proved that single-junction solar cells cannot be more than ~34% efficient, under certain assumptions. Many researchers have viewed this theoretical efficiency limit as a challenge to overcome, and have proposed a dizzying variety of techniques to surpass that limit: multijunctions, concentration, multi-exciton generation, intermediate bands, hot electrons, upconversion, downconversion, anisotropic re-radiation, etc.

In the first part of the talk, Dr. Byrnes will give a tutorial on the Shockley-Queisser limit, explaining the steps and assumptions. Then, for each of those limit-surpassing techniques, he will explain how it works, why it can (in principle) beat the S-Q limit, and whether he thinks it is promising for real-world solar cells.



Steven Byrnes, Harvard University

Dr. Steven Byrnes graduated summa cum laude from Harvard in 2007, majoring in physics and math. He then attended UC Berkeley, where he earned a PhD in physics, co-advised by Yuen-Ron Shen and Feng Wang. While there, he worked on nonlinear optical spectroscopy and laser pulse-shaping, and he developed a new architecture for photovoltaics that replaces the traditional p-n junction with the field effect. After graduating in 2012, he moved back to Harvard as a postdoc in Federico Capasso's group, where he has been working on mid-infrared energy harvesting, optical metasurfaces, and lensless imaging.


Pre-registration discount DINNER reservations must be made by 6 PM, February 16, the Monday before the meeting. Full-price reservation accepted thereafter. Walk-ins welcome at full-price. MEETING-ONLY registrations appreciated by February 18, 2015

Please make reservations online. Reservations may also be left on the answering machine at 617.584.0266. We no longer have an email address for reservations due to SPAM. When making reservation requests, please provide the following information:

  • DINNER AND MEETING or meeting only
  • Name(s) and membership status
  • Daytime phone number where you can be reached (in case of change or cancellation)


Rebeccas Cafe (Located in back of the office complex)
275 Grove Street
Auburndale, MA 02466

(617) 969-3282

(Map to Rebecca's).

Networking—5:45 PM, Dinner—6:45, Meeting—7:30 PM.


Vegetarian option available on request

Dinner Prices:

   Register on/before
 DINNER Reservation Date 
 Late Reservations 
 NES/OSA Members and their guests   $25.00 each   $30.00 
 Non-members   $30.00 (See NOTE Below)   $35.00 
 Students   $5.00   $5.00 
 Post-Docs   $15.00   $15.00 








NOTE: The NES/OSA has not changed dinner prices in several years but has been facing higher costs. We will maintain the current dinner prices for those reserving dinner on the requested date but still try to accommodate late reservations.

General Information on NES/OSA Meetings

Cancellations and No-shows:

If the meeting must be canceled for any reason, we will try to call you at the phone number you leave with your reservation. Official notice of cancellation will be on our answering machine.

We have to pay for the dinners reserved as of the Tuesday before the meeting, so no-shows eat into our cash reserve. If you will not be able to attend, please let us know as early as possible. Otherwise, no-shows will be billed.

Membership Rates:

Regular members $15.00
Student members free




NOTE: The extra $5.00 of the non-member dinner fee can be used toward membership dues if the nonmember joins and pays dues for the current year at the meeting.