Driven & thermal fields
Follow the heat and the field.
Nonequilibrium and nonreciprocal systems can produce unusual force and energy-transfer behavior. Read the temperature, bias-field, distance and environment assumptions before extending the result.
Does a proposed effect survive a complete energy and momentum account?
Observation of the dynamical Casimir effect in a superconducting circuit
Observes photon production and quantum correlations from rapidly modulated electrical boundary conditions in a superconducting circuit. It establishes a laboratory route for studying time-dependent boundaries.
Anisotropic particles near surfaces: Propulsion force and friction
Calculates fluctuation-mediated propulsion forces for small anisotropic objects out of thermal equilibrium, including objects close to a surface. It identifies a specific research avenue where geometry and thermal conditions can affect lateral forces.
Near Field Propulsion Forces from Nonreciprocal Media
Analyzes a lateral force between plates at different temperatures and shows that geometric asymmetry alone is insufficient in the studied setup: nonreciprocity is required. The arrangement is a heat engine whose efficiency remains bounded by the Carnot limit.
Propulsion force and heat transfer for nonreciprocal nanoparticles
Separates reciprocal and nonreciprocal contributions to nanoparticle heat transfer and force. It finds passivity-based limits relevant to proposed heat engines, while identifying regimes of potentially substantial forces relative to nanoparticle weight.
Support for the thermal origin of the Pioneer anomaly
The team modeled anisotropic thermal emission using spacecraft documentation and flight telemetry and independently compared the inferred recoil with navigation data. Their analysis found no statistically significant residual anomalous acceleration after accounting for the thermal recoil, showing why directional heat emission must enter a momentum budget.
Direct observation of the violation of Kirchhoff’s law of thermal radiation
Directly compares directional absorption and emission in a resonant photonic structure incorporating magneto-optic InAs. An applied magnetic field makes these quantities unequal in the same directional channel, providing experimental evidence for nonreciprocal thermal optics.
Broadband nonreciprocal thermal emissivity and absorptivity
Measures magnetically tunable nonreciprocal absorption and emission across a broader infrared band using layered InAs. Comparing two layer thicknesses links fabrication choices to measured optical behavior.
Nonreciprocal scattering and implications for thermal emission control on a mid-infrared spatiotemporally modulated metasurface
Demonstrates nonreciprocal mid-infrared scattering from a graphene-based metasurface driven by space-time modulation. Theory relates the measured scattering asymmetry to unequal thermal absorption and emission channels.