Question
Two answers required. Nicola Spaldin’s group pioneered the study of materials that exhibit these two properties, such as bismuth ferrite. For 10 points each:
[10h] Give these two properties, which rarely occur together because one is favored by empty d-shells and the other is favored by partially filled d-shells. Materials with these two properties are of interest mainly for developing ultra-low-power logic devices.
ANSWER: ferroelectric AND ferromagnetic [reject partial answers; prompt on multiferroic]
[10e] Intel’s recent MESO architecture reads out a multiferroic layer using the inverse Rashba-Edelstein effect, in which accumulation of this quantity generates current. Electrons have a magnetic moment due to this quantity, their intrinsic angular momentum.
ANSWER: spin [or spin angular momentum]
[10m] While ferromagnetic materials display nonzero magnetization, ferroelectric materials display nonzero values of this quantity in the absence of external fields. The divergence of this quantity is the bound charge.
ANSWER: polarization density [or electric polarization]
<VD, Physics>
Summary
| 2023 ARCADIA at UC Berkeley | Premiere | Y | 2 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at Carleton University | Premiere | Y | 3 | 10.00 | 67% | 33% | 0% |
| 2023 ARCADIA at Claremont Colleges | Premiere | Y | 1 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at Indiana | Premiere | Y | 5 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at RIT | Premiere | Y | 2 | 15.00 | 100% | 50% | 0% |
| 2023 ARCADIA at WUSTL | Premiere | Y | 3 | 10.00 | 100% | 0% | 0% |