Question
This technique allows the creation of petawatt-intensity laser pulses, which are used to excite plasma waves in wakefield particle accelerators that are small enough to fit on a table. For 10 points each:
[10h] Identify this technique developed by Gerard Mourou and Donna Strickland, in which a pulse generated by Q-switching or mode-locking is stretched in time and then later re-compressed in order to increase its intensity.
ANSWER: chirped-pulse amplification [accept CPA]
[10e] The stretcher grating pair introduces positive chirp, meaning this quantity for the pulse increases in time. The energy of a photon is equal to Planck’s constant times this quantity.
ANSWER: frequency [prompt on f or nu]
[10m] By stretching the pulse first, CPA bypasses a costly roadblock in which catastrophic self-focusing of laser pulses via this effect would destroy laser components. The refractive index depends on the square of the electric field in this nonlinear optical effect.
ANSWER: Kerr effect
<VD, Physics>
Summary
| 2023 ARCADIA at Duke | Emory, Duke, Yale | Y | 4 | 5.00 | 50% | 0% | 0% |
| 2023 ARCADIA at Emory | Emory, Duke, Yale | Y | 4 | 12.50 | 75% | 50% | 0% |
| 2023 ARCADIA at Imperial | Imperial | Y | 5 | 14.00 | 80% | 20% | 40% |
| 2023 ARCADIA at Maryland | Maryland, Online | Y | 3 | 6.67 | 67% | 0% | 0% |
| 2023 ARCADIA at Ohio State | Ohio State, Texas | Y | 3 | 6.67 | 67% | 0% | 0% |
| 2023 ARCADIA Online | Maryland, Online | Y | 3 | 16.67 | 67% | 67% | 33% |
| 2023 ARCADIA at Texas | Ohio State, Texas | Y | 3 | 6.67 | 67% | 0% | 0% |
Data
| Emory A | Georgia Tech A | 0 | 10 | 0 | 10 |
| Georgia A | Georgia Tech B | 0 | 0 | 0 | 0 |
| Georgia Tech C | Georgia B | 0 | 10 | 10 | 20 |
| Georgia Tech D | Tennessee A | 0 | 10 | 10 | 20 |