Enhancement of specific absorption rate in lossy dielectric objects using a slab of left-handed material.
An enhancement of the specific absorption rate (SAR) inside a lossy dielectric object has been investigated theoretically based on a slab of left-handed medium (LHM). In order to make an accurate analysis of SAR distribution, a proper Green's function involved in the LHM slab is proposed, from which an integral equation for the electric field inside the dielectric object is derived. Such an integral equation has been solved accurately and efficiently using the conjugate gradient method and the fast Fourier transform. We have made a lot of numerical experiments on the SAR distributions inside the dielectric object excited by a line source with and without the LHM slab. Numerical experiments show that SAR can be enhanced tremendously when the LHM slab is involved due to the proper usage of strong surface waves, which will be helpful in the potential biomedical applications for hyperthermia. The physical insight for such a phenomenon has also been discussed.
Center for Computational Electromagnetics and the State Key Laboratory of Millimeter Waves, Department of Radio Engineering, Southeast University, Nanjing 210096, People's Republic of China.
Lei
L
Zhao
Tie Jun
TJ
Cui
D000042:Absorption; D000818:Animals; D001822:Body Burden; D001831:Body Temperature / Q000502:physiology* / Q000528:radiation effects; D003198:Computer Simulation; D003238:Connective Tissue / Q000502:physiology* / Q000528:radiation effects*; D004574:Electromagnetic Fields; D004735:Energy Transfer / Q000502:physiology*; D006358:Hot Temperature; D006801:Humans; D008954:Models, Biological; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D012062:Relative Biological Effectiveness