Nernst–Ettingshausen generator

Matrix context

D = disequilibrium row · C = coupling family column. A cell reads the state of the atlas for that pair.

D.01 × C.01 · Temperature gradient × Thermoelectricfamily: Thermoelectric

Measured or reported performance

Summary figures only; no datum-level record yet. Each figure below is a reviewed summary, not a single measurement.

notes

Bi–Sb alloys in fields of a few tesla at cryogenic temperatures; laboratory devices only

Typed bounds on this route

Every limit the atlas holds for this route, as constraint records: reached through bounded_by claims on the route's own entities. Hard bounds (an upper bound or a formula) decide the thermodynamic-bound check above; benchmarks, constitutive relations and resource limits are listed and never decisive. No prose limit exists anywhere (pass 42).

• Carnot limit · formula-bound · hard, applies to this route
  η ≤ 1 − T_c/T_h for any heat engine between reservoirs at T_h and T_c

Steps

1. 01
   Temperature gradient —drives→ Nernst effectestablishedclaim record

   thermal → electrical · loss to thermal

   E_y = N · B_z · ∇T_x · N·B (Nernst coefficient × field), in V/K [V/K]

   • a magnetic field perpendicular to the temperature gradient; the transverse field is proportional to B and ∇T

   solid · conductor required · magnetic field required · temperature gradient required

   refs [1] [2]
2. 02
   Nernst effect —produces→ Charge carriersestablishedclaim record

   electrical → electrical

   refs [2] [3]
3. 03
   Charge carriers —converts into→ Electrical workestablishedclaim record

   electrical → electrical · loss to thermal

   • carriers driven through an external load at the potential difference the source maintains

   refs [4]

Evidence for the complete composition · 2

1. [5]
   D. M. Rowe (ed.). Thermoelectrics Handbook: Macro to Nano (2006)

   CRC Press · doi:10.1201/9781420038903 · crossref ✓ 2026-09-19 · record
2. [2]
   H. B. Callen. The application of Onsager's reciprocal relations to thermoelectric, thermomagnetic, and galvanomagnetic effects (1948)

   Physical Review 73, 1349 · doi:10.1103/PhysRev.73.1349 · crossref ✓ 2026-09-19 · record

Evidence for the constituent relations · 4

1. [1]
   A. von Ettingshausen, W. Nernst. Ueber das Auftreten electromotorischer Kräfte in Metallplatten, welche von einem Wärmestrome durchflossen werden und sich im magnetischen Felde befinden (1886)

   Annalen der Physik 265, 343–347 · doi:10.1002/andp.18862651010 · crossref ✓ 2026-09-19 · record
2. [2]
   H. B. Callen. The application of Onsager's reciprocal relations to thermoelectric, thermomagnetic, and galvanomagnetic effects (1948)

   Physical Review 73, 1349 · doi:10.1103/PhysRev.73.1349 · crossref ✓ 2026-09-19 · record
3. [3]
   H. J. Goldsmid. Introduction to Thermoelectricity (2nd ed.) (2016)

   Springer Series in Materials Science 121 · doi:10.1007/978-3-662-49256-7 · crossref ✓ 2026-09-19 · record
4. [4]
   N. W. Ashcroft, N. D. Mermin. Solid State Physics (1976)

   Holt, Rinehart and Winston · book, no DOI · record