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Colossal Dielectric Constants And Mach Propulsion
From NextBigFuture.com
The development of new materials with high ("colossal") dielectric constants is prerequisite for the further miniaturization of electronic devices. The search for such materials and especially the clarification of the microscopic mechanisms that can lead to an enhancement of this material parameter are important goal.
Most of the capacitive materials employed in modern electronics have relatively low values of ε' of the order of 10. Currently applied materials with higher ε' are mostly based on ferroelectrics, which, however, are hampered by various setbacks limiting their applicability.
Colossal dielectric constants (CDCs), i.e. values of ε' exceeding 1000, are found in various materials and can be caused by different physical processes.
In recent times there are strong efforts to find new high-ε' materials with better properties and indeed there are some promising candidates. The most prominent CDC material is CaCu 3Ti 4O 12 (CCTO) [Sub00,Hom01]. Compared to ferroelectrics-based dielectrics, CCTO exhibits a nearly temperature independent CDC around room temperature, which is highly advantageous for possible technical application (Fig. 2). Only at low temperatures and/or high frequencies it shows a marked and strongly frequency-dependent decrease of ε' from values up to 10³5 to magnitudes of the order of 100.
Mach Effect Propulsion
Much of the work is continuing to use the same sorts of materials and designs from more than a decade ago. I'm hoping that when Jim Woodward's book comes out, we'll see an explosion of interest that opens up some finding and allows access to new materials like single crystal CCTO, that has k values up to 100,000. Right now, Jim is using PZT that has a k of less than 1,000. Force generated by his UFG scales with the square of the k, so you can see why access to CCTO could be a breakthrough that increases mach effect by 10,000.
CCTO is fabulous stuff in a single crystal, but there are no commercial providers for single crystal CCTO. With BaTiO3, you can find cheap single crystal targets but they are unpolarized and have no electrodes sputtered on. That is an obtainable goal if one can find a cheap way to sputter.
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