Publications (10)
Multi-scale time-resolved electron diffraction: A case study in moiré materials
C. J. R. Duncan, M. Kaemingk, W. H. Li +16
Ultrafast-optical-pump -- structural-probe measurements, including ultrafast electron and x-ray scattering, provide direct experimental access to the fundamental timescales of atom…
Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at mega-gauss magnetic fields
M. Zybert, M. Marchewka, E. M. Sheregii +8
Landau levels and shallow donor states in multiple GaAs/AlGaAs quantum wells (MQWs) are investigated by means of the cyclotron resonance at mega-gauss magnetic fields. Measurements…
First science with SALT: peering at the accreting polar caps of the eclipsing polar SDSS J015543.40+002807.2
D. O'Donoghue, D. A. H. Buckley, L. A. Balona +48
We describe briefly the properties of the recently completed Southern African Large Telescope (SALT), along with its first light imager SALTICAM. Using this instrument, we present…
BICEP2 and Keck Array operational overview and status of observations
R. W. Ogburn, P. A. R. Ade, R. W. Aikin +50
The BICEP2 and Keck Array experiments are designed to measure the polarization of the cosmic microwave background (CMB) on angular scales of 2-4 degrees (l=50-100). This is the reg…
Point-to-Point Coulomb Effects in High Brightness Photoelectron Beamlines for Ultrafast Electron Diffraction
M. Gordon, S. B. van der Geer, J. Maxson +1
In an effort to increase spatial and temporal resolution of ultrafast electron diffraction and microscopy, ultra-high brightness photocathodes are actively sought to improve electr…
A Semantic Framework for Enabling Radio Spectrum Policy Management and Evaluation
H. Santos, A. Mulvehill, J. S. Erickson +11
Because radio spectrum is a finite resource, its usage and sharing is regulated by government agencies. These agencies define policies to manage spectrum allocation and assignment…
Photoinduced twist and untwist of moiré superlattices in TMDC heterobilayers
C. J. R. Duncan, A. C. Johnson, I. Maity +15
Two-dimensional moiré materials are formed by artificially stacking atomically thin monolayers. A wealth of correlated and topological quantum phases can be engineered via precise…
Four-Dimensional Emittance Measurements of Ultrafast Electron Diffraction Optics Corrected Up to Sextupole Order
M. Gordon, W. H. Li, M. B. Andorf +7
Ultrafast electron diffraction (UED) is a technique in which short-pulse electron beams can probe the femtosecond-scale evolution of atomic structure in matter driven far from equi…
Cyclotron and combined phonon-assisted resonances in double-well heterostructure InGaAs/InAlAs at megagauss magnetic fields
M. Zybert, M. Marchewka, E. M. Sheregii +7
Experiments on resonances of conduction electrons in InGaAs/InAlAs double quantum wells at megagauss magnetic fields in the Faraday geometry are reported. We observe new cyclotron…
A kiloelectron-volt ultrafast electron micro-diffraction apparatus using low emittance semiconductor photocathodes
W. H. Li, C. J. R. Duncan, M. B. Andorf +10
We report the design and performance of a time-resolved electron diffraction apparatus capable of producing intense bunches with simultaneously single digit micron probe size, long…