39 citations · 138 across the 8 of their papers we have counts for
8 papers
A Hunt for Magnetic Signatures of Hidden-Photon and Axion Dark Matter in the Wilderness
Ibrahim A. Sulai, Saarik Kalia, Ariel Arza +17
Earth can act as a transducer to convert ultralight bosonic dark matter (axions and hidden photons) into an oscillating magnetic field with a characteristic pattern across its surf…
Quenched magnetic moment in Mn-doped amorphous Si (\textit{a}-MnSi) across the metal-insulator transition
Li Zeng, E. Helgren, R. Islam +4
The magnetic and electrical transport properties of Mn-doped amorphous silicon (\textit{a-}MnSi) thin films have been measured. The magnetic susceptibility obeys the…
Microstructure, magneto-transport and magnetic properties of Gd-doped magnetron-sputtered amorphous carbon
L. Zeng, E. Helgren, F. Hellman +3
The magnetic rare earth element gadolinium (Gd) was doped into thin films of amorphous carbon (hydrogenated \textit{a}-C:H, or hydrogen-free \textit{a}-C) using magnetron co-sputte…
'Taxonomy' of Electron Glasses
N. P. Armitage, E. Helgren, G. Gruner
We report measurements of the real and imaginary parts of the AC conductivity in the quantum limit, \hbar ω> k_B T of insulating nominally uncompensated n-type silicon. The observe…
The Frequency Dependent Conductivity of Electron Glasses
E. Helgren, N. P. Armitage, G. Gruner
Results of DC and frequency dependent conductivity in the quantum limit, i.e. hw > kT, for a broad range of dopant concentrations in nominally uncompensated, crystalline phosphorou…
Dipole relaxation losses in DNA
M. Briman, N. P. Armitage, E. Helgren +1
The electrodynamic response of DNA in the millimeter wave range is investigated. By performing measurements under a wide range of humidity conditions and comparing the response of…