Source-linked AI summary
Experimental demonstration of a multiphysics cloak: manipulating heat flux and electric current simultaneously
Yungui Ma, Yichao Liu, Muhammad Raza, Yudong Wang, Sailing He
TL;DR
Prior cloaking work largely addressed single physical systems, motivating whether one device could control multiple phenomena. The paper develops a bilayer electric-thermal cloak and reports experimental dual cloaking for current and heat, with numerical verification under point-source excitation.
Problem
The paper addresses whether different physical equations can be coupled in one device to realize multiple physical phenomena, extending cloaking beyond single-system implementations.
Method
The study uses a two-dimensional static-conduction bilayer shell combining an air cavity with a high-conductivity solid, with parameters derived from electric and thermal Laplace equations.
Results
The device experimentally demonstrates cloaking of both electric current and heat flux under uniform excitation and numerically maintains the effect under point-source excitation.
Takeaways & Limitations
The results support multiphysics devices that simultaneously manipulate electric current and heat flux, with possible relevance to solar-cell systems and on-chip integration.
Abstract
from arXiv · showhide
In past years, triggered by their successful realizations in electromagnetics, invisible cloaks have experienced rapid development and have been widely pursued in many different fields, though so far only for a single physical system. In this letter we made an unprecedented experimental attempt to show a multidisciplinary framework designed on the basis of two different physical equations. The proposed structure has the exceptional capability to simultaneously control two different physical phenomena according to the predetermined evolution scenarios. As a proof of concept, we implemented an electric-thermal bifunctional device that can guide both electric current and heat flux "across" a strong 'scatter' (air cavity) and restore their original diffusion directions as if nothing exists along the paths, thus rending dual cloaking effects for objects placed inside the cavity. This bifunctional cloaking performance is also numerically verified for a point-source nonuniform excitation. Our results and the fabrication technique presented here will help broaden the current research scope for multiple disciplines and may pave a prominent way to manipulate multiple flows and create new functional devices, e.g., for on-chip applications.
Figure 1
Figure 1 presents the bilayer cloak design, its conductivity-dependent parameters, and a fabricated sample device.
- The schematic combines an air cavity, a high-conductivity medium, and a bilayer cloak to control heat or current flow.The red lines indicate conduction flow, while R1 and R2 denote the inner and outer shell radii.
Figure 2
Figure 2 depicts numerical and measured electric potential distributions for samples without and with the cloaking shell, alongside the measurement setup.
- The figure compares electric potential profiles without and with a cloaking shell and shows the corresponding measurement arrangement.A 1 V bias is applied across the sample, and voltage probes map the spatial potential distribution.
Figure 3
Figure 3 shows simulated and measured temperature fields for heat-flux cloaking, including the controlled thermal source, sink, and infrared imaging setup.
- The figure compares simulated temperature profiles without and with a cloaking shell and presents the thermal measurement setup.The source and sink are maintained at 50 °C and 30 °C, respectively, while an infrared camera records the equilibrium temperature field.
Figure 4
Figure 4 numerically evaluates bifunctional cloaking under point-source excitation for two shell-radius ratios and compares cloaks with cavities and empty backgrounds.
- The figure compares cloak, cavity, and empty-background cases for R2/R1 = 2 and 1.02 under a point-source external field.The comparison applies equally to electric current and heat flux.