Question
Photons in semiconductor lasers such as VCSELs (“VICK-sulls”) are produced by radiative recombination of electrons and these particles. For 10 points each:
[10e] Name these positively-charged quasiparticles that are the majority carriers in p-type semiconductors.
ANSWER: electron holes [reject “holons”]
[10m] Recombination of electrons and holes occurs in one of these heterostructures sandwiched between two sets of Bragg reflectors in the VCSEL geometry. Layers of different semiconductors with different bandgaps provide an effective potential for confinement in these heterostructures.
ANSWER: quantum wells [prompt on wells]
[10h] A superlattice of quantum wells appears in this other design of semiconductor lasers proposed by Kazarinov and Suris. In this design, electrons tunnel between quantum wells and emit light by intersubband (“inter-sub-band”) transitions.
ANSWER: quantum cascade laser [prompt on QCL]
<DC, Physics>
Data
Summary
| Tournament | Edition | Exact Match? | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|---|---|
| 2024 Chicago Open | 07/28/2024 | Y | 12 | 12.50 | 92% | 8% | 25% |