differnec between bulk absoption and localised surface plasmon absorption
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Please bear with me while I try to ask my question. The way I understand plasmonics currently is the following:
A plasmon may be defined as the quanta of oscillation of plasma. In my case, we'll let the plasma be the electron sea/cloud in a metal. Therefore, a bulk plasmon is the longitudinal oscillation of the entire object's electron cloud (therefore requiring a finite size in at least one dimension). A surface plasmon (SP) is the oscillation (parallel to the surface) of the surface electrons in an object. A surface plasmon polariton (SPP) simply refers to the definition of "polariton," and means that an electromagnetic wave is coupled to the surface plasmon. Often, it seems that SP and SPP are used interchangeably, even though there is a difference in their definition. Lastly, a localized surface plasmon is a surface plasmon which cannot propagate until it dies out, but instead is confined to an object which is finite in every dimension (i.e. nanoparticle, nanorod, etc.).
Wikipedia states that "a free-space photon from air cannot couple directly to an SPP", and mentions that in order to detect a SPP, one must use the Kretschmann or Otto configuration with a prism.
1) Does this mean that a thin film, which would be "infinite" in two dimensions and finite in the other, cannot experience surface plasmon resonance unless it is in a lab environment in one of those configurations? It seems like, given Wikipedia's definition, a film could then not be used for optical absorption purposes.
2) If this is the case and a film cannot be used, what about localized surface plasmons make it so that it can be coupled with a free-space photon in air?
A plasmon may be defined as the quanta of oscillation of plasma. In my case, we'll let the plasma be the electron sea/cloud in a metal. Therefore, a bulk plasmon is the longitudinal oscillation of the entire object's electron cloud (therefore requiring a finite size in at least one dimension). A surface plasmon (SP) is the oscillation (parallel to the surface) of the surface electrons in an object. A surface plasmon polariton (SPP) simply refers to the definition of "polariton," and means that an electromagnetic wave is coupled to the surface plasmon. Often, it seems that SP and SPP are used interchangeably, even though there is a difference in their definition. Lastly, a localized surface plasmon is a surface plasmon which cannot propagate until it dies out, but instead is confined to an object which is finite in every dimension (i.e. nanoparticle, nanorod, etc.).
Wikipedia states that "a free-space photon from air cannot couple directly to an SPP", and mentions that in order to detect a SPP, one must use the Kretschmann or Otto configuration with a prism.
1) Does this mean that a thin film, which would be "infinite" in two dimensions and finite in the other, cannot experience surface plasmon resonance unless it is in a lab environment in one of those configurations? It seems like, given Wikipedia's definition, a film could then not be used for optical absorption purposes.
2) If this is the case and a film cannot be used, what about localized surface plasmons make it so that it can be coupled with a free-space photon in air?
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