The first observation of a giant nonlinear Nernst Effect in trilayer graphene, a non-magnetic material, without applying external magnetism

https://phys.org/news/2025-07-giant-nonlinear-nernst-effect-trilayer.html

"applied sinusoidal current to heater, inducing temperature gradient fluctuating 2X frequency... 4th harmonic transverse voltage, 2nd-order response to temperature gradient unlike conventional linear response... up to 300 µVK-1 giant effective Nernst coefficient at 2 K in ABA trilayer graphene, 2 orders magnitude larger... more compact thermoelectric devices... future: room temperature instead of <12°K, explore other time-reversal invariant/ non-centrosymmetric materials, use of 3D instead of 2D materials"