Left Handed Materials Based on Magnetic Nanocomposites
Abstract
A new measurement technique has been proposed to determine the sign of the index of refraction in thin film samples. We have observed signature of negative index in NiFe-SiO2 magnetic granular materials and in NiFe/SiO2 multilayers. However, the signal is weak due to thin sample and is very much sample dependent, we could not consistently confirm the properties. We have theoretically established selection criteria for magnetic materials and their structures to achieve LHMs or NIMs. We have theoretically proposed several new structures that show negative index of refraction (NIMs). These structures include: 1) Double negative materials (DNMs) for LHMs: E/M multilayers consisting of alternating negative e and negative u layers. 2) Single negative materials (SNMs) for NIMs: Ferrite/(Semiconductor or Oxides) multilayer with negative u. We have developed a theory that unifies DNMs and SNMs as a function of two fundamental material parameters: quality factors for permittivity (Qe=e'/e") and permeability (Qu=u'u").
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 18, 2006
- Accession Number
- ADA461023
Entities
People
- John Xiao