59 citations · 151 across the 9 of their papers we have counts for
9 papers
An algebraic RF sheath model for all excitation waveforms and amplitudes, and all levels of collisionality
A. E. Elgendy, H. Hatefinia, T. Hemke +5
The boundary sheath of a low temperature plasma comprises typically only a small fraction of its volume but is responsible for many aspects of the macroscopic behavior. A thorough…
Singular field response and singular screening of vacancies in antiferromagnets
Alexander Wollny, Eric C. Andrade, Matthias Vojta
For isolated vacancies in ordered local-moment antiferromagnets we show that the magnetic-field linear-response limit is generically singular: The magnetic moment associated with a…
Numerical study of secondary electron emission in a coaxial radio-frequency driven plasma jet at atmospheric pressure
Torben Hemke, Jan Trieschmann, Alexander Wollny +2
In this work we investigate a numerical model of a coaxial RF-driven plasma jet operated at atmospheric pressure. Due to the cylindrical symmetry an adequate 2-D representation of…
Spatially resolved simulation of a radio frequency driven micro atmospheric pressure plasma jet and its effluent
Torben Hemke, Alexander Wollny, Markus Gebhardt +2
Radio frequency driven plasma jets are frequently employed as efficient plasma sources for surface modification and other processes at atmospheric pressure. The radio-frequency dri…
Self-pulsing of a micro thin cathode discharge
Alexander Wollny, Markus Gebhardt, Torben Hemke +2
Microplasmas operated at atmospheric pressure show a number of peculiar dynamic phenomena. One of these phenomena is self-pulsing, which is characterized by intrinsic pulsing behav…
Fractional impurity moments in two-dimensional non-collinear magnets
Alexander Wollny, Lars Fritz, Matthias Vojta
We study dilute magnetic impurities and vacancies in two-dimensional frustrated magnets with non-collinear order. Taking the triangular-lattice Heisenberg model as an example, we u…
Ionization wave propagation on a micro cavity plasma array
Alexander Wollny, Torben Hemke, Markus Gebhardt +7
Microcavity plasma arrays of inverse pyramidal cavities have been fabricated in p-Si wafers. Each cavity acts as a microscopic dielectric barrier discharge. Operated at atmospheric…
Inter-layer Josephson coupling in stripe-ordered superconducting cuprates
Alexander Wollny, Matthias Vojta
Motivated by experiments on LBCO-1/8 which suggest that stripe order co-exists with two-dimensional pairing without inter-layer phase coherence over an extended range of temperatur…
Photoemission signatures of valence-bond stripes in cuprates: Long-range vs. short-range order
Alexander Wollny, Matthias Vojta
Recent experiments indicate that the tendency toward the formation of unidirectional charge density waves ("stripes") is common to various underdoped cuprates. We discuss momentum-…