Dear community. As far as I understand, the dielectric confinement problem is scale invariant, while the quantum confinement problem has a length scale defined by the Bohr radius.
I have been trying to understand some experimental results in terms of the change in dielectric confinement of the system: one material phase, with a higher permittivity, embedded into a secondary phase with a lower permittivity. After some treatment, the phases distribution change, with the first phase increasing its volume ratio. This will be consistent with changes in dielectric confinement. The problem is that the scale of the phases is way above the Bohr radius of the specific material, and all the literature I have found, deals with dielectric confinement only for very confined systems, within the quantum confined scale.
Can anyone point me to some literature that deals with the scale of dielectric confinement?
Thanks.
The dielectric confinement is exploited in the dielectric waveguides such as the glass fiber. The confinement is based on the total reflection at the boundary of the two materials. It requires a boundary with two different dielectric constant and a an incident angle greater than that required for the total reflection. So the confinement may occur in a fiber with a dimensions in the order of the ligfht wavelength.
Best wishes
The question is how you define 'dielectric confinement': what exactly do you want to confine? In classical dielectric theory it is the plasmon that is referred to, which has an extension larger much than a typical electron confinement because it describes a collective excitation of many valence electrons so is a multi-atom phenomenon.
The dielectric confinement is exploited in the dielectric waveguides such as the glass fiber. The confinement is based on the total reflection at the boundary of the two materials. It requires a boundary with two different dielectric constant and a an incident angle greater than that required for the total reflection. So the confinement may occur in a fiber with a dimensions in the order of the ligfht wavelength.
Best wishes
Dielectric confinement is usually referred to the confinement of the E&M wave, where the relevant scale is the wavelength of the light. Quantum confinement is commonly referred to the confinement of the electronic wave, where the relevant scale is the de Broglie wavelength (not Bohr radius, which you might have seen).
Of course, in the former case, the contrast of the dielectric function is important, and in the latter case, the barrier height is important.
Two confinements occur in different length scales: wavelength of light (e.g., 500 nm) vs. wavelength of electron (e.g., 50 A).
Fundamentally, in both cases, the contrast between the two materials arises from the difference in the electronic structure of the materials. Usually the same material combination can offer confinement to both light and electron. You just need to make the double heterostructure in the appropriate length scale relevant to the purpose. For instance, Al(x)Ga(1-x)As can be used to confine both electron and light in GaAs.
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