Analysis of gain and bandwidth for a dielectric Cherenkov maser with a plasma layer, operating in a hybrid plasma mode

The linearised nonlocal kinetic equation is solved analytically for impurity scattering. The resulting response function provides the conductivity, plasma oscillation and Fermi momentum. It is found that virial corrections nearly compensate the wave-function renormalizations rendering the conductivity and plasma mode unchanged. Due to the appearance of the correlated density, the Luttinger theorem does not hold and the screening length is influenced. Explicit results are given for a typical semiconductor. Elastic scattering of electrons by impurities is the simplest but still very interesting dissipative mechanism in semiconductors. Its simplicity follows from the absence of the impurity dynamics, so that individual collisions are described by the motion of an electron in a fixed potential.

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Non-linear Terahertz driving of plasma waves in layered cuprates

Nature Communications ◽

10.1038/s41467-021-21041-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Francesco Gabriele ◽

Mattia Udina ◽

Lara Benfatto

Keyword(s):

Low Frequency ◽

Plasma Waves ◽

Meissner Effect ◽

High Energy ◽

Plasma Mode ◽

Light Pulses ◽

High Frequency Plasma ◽

Non Linear ◽

Out Of Plane ◽

Layered Cuprates

AbstractThe hallmark of superconductivity is the rigidity of the quantum-mechanical phase of electrons, responsible for superfluid behavior and Meissner effect. The strength of the phase stiffness is set by the Josephson coupling, which is strongly anisotropic in layered cuprates. So far, THz light pulses have been used to achieve non-linear control of the out-of-plane Josephson plasma mode, whose frequency lies in the THz range. However, the high-energy in-plane plasma mode has been considered insensitive to THz pumping. Here, we show that THz driving of both low-frequency and high-frequency plasma waves is possible via a general two-plasmon excitation mechanism. The anisotropy of the Josephson couplings leads to markedly different thermal effects for the out-of-plane and in-plane response, linking in both cases the emergence of non-linear photonics across Tc to the superfluid stiffness. Our results show that THz light pulses represent a preferential knob to selectively drive phase excitations in unconventional superconductors.

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Axisymmetric plasma mode in disk with two-dimensional electron gas

Journal of Physics Conference Series ◽

10.1088/1742-6596/1686/1/012052 ◽

2020 ◽

Vol 1686 ◽

pp. 012052

Author(s):

D A Rodionov ◽

I V Zagorodnev ◽

A A Zabolotnykh ◽

V A Volkov

Keyword(s):

Electron Gas ◽

Two Dimensional ◽

Dimensional Electron ◽

Two Dimensional Electron Gas ◽

Plasma Mode ◽

Dimensional Electron Gas

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Surface Immobilization of Synthetic Proteins Via Plasma Polymer Interlayers

MRS Proceedings ◽

10.1557/proc-544-9 ◽

1998 ◽

Vol 544 ◽

Cited By ~ 6

Author(s):

Hans J Griesser ◽

Keith M McLean ◽

Gerrit J Beumer ◽

Xiaoyi Gong ◽

Peter Kingshot ◽

...

Keyword(s):

Carboxylic Acid ◽

Cell Attachment ◽

Plasma Layer ◽

Polymeric Materials ◽

Covalent Immobilization ◽

Biologically Active ◽

Plasma Polymer ◽

Rf Plasma ◽

Bulk Materials ◽

Synthetic Proteins

AbstractCoatings of biologically active molecules on synthetic ”bulk“materials are of much interest for biomedical applications since they can in principle elicit specific, predictable. controlled responses of the host environment to an implanted device. However, issues such as shelf life. storage conditions, biological safety, and enzymatic attack in the biological environment must be considered; synthetic proteins may offer advantages. In this study we investigated the covalent immobilization onto polymeric materials of synthetic proteins which possess some properties that mimic those of the natural protein collagen, particularly the ability to form triple helical structures, and thus may provide similar bio-responses while avoiding enzymatic degradation. In order to perform immobilization of these collagen-like molecules (CLMs) under mild reaction conditions, the bulk materials are first equipped with suitable surface groups using rf plasma methods. Plasma polymer interlayers offer advantages as versatile reactive platforms for the immobilization of proteins and other biologically active molecules. Application of a thin plasma polymer coating from an aldehyde monomer is particularly suitable as it enables direct immobilization of CLMs by reaction with their terminal amine groups, using reductive amination chemistry. An alternative route is via plasma polymer layers that contain carboxylic acid groups and using carbodiimnide chemistry. A third route makes use of alkylamme plasma polymer interlayers, which are less process sensitive than aldehyde and acid plasma coatings. A layer of poly-carboxylic acid compounds such as carboxylic acid terminated PAMAM-starburst dendrimers or carboxymethylated dextran is then attached by carbodiimide chemistry onto the amine plasma layer. Amine-terminated CLMs can then be immobilized onto the poly-carboxylic acid layer. Surface analytical methods have been used to characterize the immobilization steps and to assess the surface coverage. Initial cell attachment and growth assays indicate that the biological performance of the CLMs depends on their amino acid sequence.

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