Temporal temperature change —drives→ Pyroelectric effect

Conditions

• the temperature of the polar material must change in time (dT/dt ≠ 0); a static spatial temperature gradient alone produces no pyroelectric current
• the material must be below its Curie temperature

Constitutive relation

ΔP = p · ΔT

ΔT is the material's temperature change between two times, not a spatial temperature difference.

Evidence · 3

1. [1]
   S. B. Lang. Pyroelectricity: from ancient curiosity to modern imaging tool (2005)

   Physics Today 58(8), 31–36 · doi:10.1063/1.2062916 · crossref ✓ 2026-09-19 · record
2. [2]
   R. W. Whatmore. Pyroelectric devices and materials (1986)

   Reports on Progress in Physics 49, 1335 · doi:10.1088/0034-4885/49/12/002 · crossref ✓ 2026-09-19 · record
3. [3]
   C. R. Bowen et al.. Pyroelectric materials and devices for energy harvesting applications (2014)

   Energy & Environmental Science 7, 3836–3856 · doi:10.1039/C4EE01759E · crossref ✓ 2026-09-19 · record

Matrix cells this relation feeds

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

Uses of this claim

• Pyroelectric harvesterdemonstrated · 3 steps

• Changing magnetic flux → Magnetocaloric effect → Temporal temperature change → Pyroelectric effect → Separated surface charge → Electrical work5/5 established · extends a recorded pathway
• Mechanical stress or strain → Elastocaloric effect → Temporal temperature change → Pyroelectric effect → Separated surface charge → Electrical work5/5 established · extends a recorded pathway
• Changing electric field → Electrocaloric effect → Temporal temperature change → Pyroelectric effect → Separated surface charge → Electrical work5/5 established · same energy form
• Temperature gradient → Thermal expansion → Mechanical stress or strain → Elastocaloric effect → Temporal temperature change → Pyroelectric effect → Separated surface charge → Electrical work7/7 established · extends a recorded pathway
• Pressure gradient → Elastic deformation → Mechanical stress or strain → Elastocaloric effect → Temporal temperature change → Pyroelectric effect → Separated surface charge → Electrical work7/7 established · extends a recorded pathway
• Mechanical vibration → Resonant vibration → Mechanical stress or strain → Elastocaloric effect → Temporal temperature change → Pyroelectric effect → Separated surface charge → Electrical work7/7 established · extends a recorded pathway
• Mechanical vibration → Elastic deformation → Mechanical stress or strain → Elastocaloric effect → Temporal temperature change → Pyroelectric effect → Separated surface charge → Electrical work7/7 established · extends a recorded pathway

Notes

Re-spelled in loop-3 pass 30 from the temperature-gradient row, where it had sat as an indexing compromise, onto the temporal temperature change that is its physical driver.

Cite this claim

Physical Transformation Atlas (2026). claim claim:pyro-drives: Temporal temperature change —drives→ Pyroelectric effect. Dataset revision rbfbfcbb70e57 (hash of the canonical data). https://physical-transformation-atlas.wldud5192.workers.dev/claim/pyro-drives

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