arXiv subjects

Nathan Woollett

Publications and source records attributed to Nathan Woollett.

3 recordsLinked to original sources

arXiv2020

Using Cyclotron Radiation Emission for Ultra-high Resolution X-Ray Spectroscopy

Cyclotron Radiation Emission Spectroscopy (CRES) is an approach to measuring the energy of an electron trapped in an externally applied magnetic field. The bare electron can come from different interactions, including photoelectric absorption, Compton scatters, beta decay, and pair production. CRES relies on measuring the frequency of the electron's cyclotron motion, and because the measurement times extend over $10^6$-$10^7$ cycles, the energy resolution is on the order of a single electronvolt. To date, CRES has only been performed on internal beta-emitting radioisotopes, but the technology can be applied to X-ray spectrometery through appropriate selection of a target gas and sufficient intensity of the distinct X-ray source. The applications of this technology range from high-precision measurements of atomic energy levels, to calibrations of basic science experiments, to trace element identification. In this work we explore the use of CRES for X-ray spectroscopy within the rubric of measuring the energy levels of argon, although the principles are broadly applicable to many other situations. The issues we explore include target material, density, electron trapping depth, noise levels, and overall efficiency. We also discuss spectral deconvolution and how the multiple peaks obtained from a single target / source pair can be used to enhance the robustness of the measurement.

physics.atom-ph↗

arXiv2017

High-Kinetic Inductance Additive Manufactured Superconducting Microwave Cavity

Investigations into the microwave surface impedance of superconducting resonators have led to the development of single photon counters that rely on kinetic inductance for their operation. While concurrent progress in additive manufacturing, `3D printing', opens up a previously inaccessible design space for waveguide resonators. In this manuscript, we present results from the first synthesis of these two technologies in a titanium, aluminum, vanadium (Ti-6Al-4V) superconducting radio frequency resonator which exploits a design unattainable through conventional fabrication means. We find that Ti-6Al-4V has two distinct superconducting transition temperatures observable in heat capacity measurements. The higher transition temperature is in agreement with DC resistance measurements. While the lower transition temperature, not previously known in literature, is consistent with the observed temperature dependence of the superconducting microwave surface impedance. From the surface reactance, we extract a London penetration depth of $8\pm3μ$m - roughly an order of magnitude larger than other titanium alloys and several orders of magnitude larger than other conventional elemental superconductors. This large London penetration depth suggests that Ti-6Al-4V may be a suitable material for high kinetic inductance applications such as single photon counting or parametric amplification used in quantum computing.

cond-mat.supr-con↗

arXiv2015

Preliminary Results of the CASCADE Hidden Sector Photon Search

Light shining through a wall experiments can be used to make measurements of photon-WISP couplings. The first stage of the CASCADE experiment at the Cockcroft Institute of Accelerator Science and Technology is intended to be a proof-of-principle experiment utilising standard microwave technologies to make a modular, cryogenic HSP detector to take advantage of future high-power superconducting cavity tests. In these proceedings we will be presenting the preliminary results of the CASCADE LSW experiment showing a peak expected exclusion of $1.10 \times 10^{-8}$ in the mass range from 1.96$μ$eV to 5.38$μ$eV, exceeding current limits.

physics.ins-det↗