Dr
Gianpaolo Carosi
(Lawrence Livermore National Laboratory)
10/01/2017, 09:00
In this talk I will discuss the motivation behind this workshop by introducing the dark matter axion and the haloscope technique to search for it. This technique uses microwave cavities to resonantly enhance the conversion rate of axions to potentially detectable levels. I will layout the number of design challenges facing experimental efforts moving forward.
Dr
Frank Krawczyk
(Los Alamos National Laboratory)
10/01/2017, 09:30
The numerical design presentation addresses two topics: (1) Numerical Methods that include resonator design basics, introduction to Finite Difference, Finite Element and other methods, and (2) Introduction to Simulation Software that covers 2D and 3D software tools and their applicability, concepts for problem descriptions, interaction with particles, couplers, mechanical and thermal design,...
Nick Materise
(Lawrence Livermore National Laboratory)
10/01/2017, 13:30
Superconducting qubits have matured from platforms demonstrating and manipulating macroscopic coherent quantum states to realizing exotic quantum states, running surface error correction codes, and single photon detection to name a few recent milestones. This talk will review the fundamentals of circuit QED related to the design and simulation of superconducting qubits. A brief overview of how...
Mr
Ian Stern
(University of Florida)
10/01/2017, 14:05
Axion haloscope detectors use microwave cavities permeated by a magnetic field to resonate photons converted from axions via the Primackoff effect. The sensitivity of a detector is proportional to the coupling of the cavity’s search mode to the axion conversion. Transverse symmetry breaking is used to tune the search modes for scanning across a range of axion masses. However, computer...
Nicholas Rapidis
(University of California, Berkeley)
10/01/2017, 14:40
Microwave cavities for a Sikivie-type axion search are subject to several challenging constraints. In the fabrication and operation of such cavities, often used at frequencies where the resonator is highly overmoded, it is important to be able to reliably identify the symmetry of the mode of interest, confirm its form factor, and to determine the frequency ranges where mode crossings with...
Mark Jones
(Pacific Northwest National Laboratory)
10/01/2017, 15:45
This informal session will provide an introductory tutorial on the use of Ansys High Frequency Structure Simulator (HFSS) with a live demonstration of example models. Specific features relevant to achieving accurate cavity and antenna simulation results will be highlighted.
Dr
Yonatan Kahn
(Princeton University)
11/01/2017, 09:00
In the long-wavelength regime, axion interactions with a static magnetic field can be described in terms of an effective current which sources a small oscillating magnetic field. I will describe a new experiment (ABRACADABRA) to detect this axion effective current which can operate with either broadband or resonant readout of the signal. Inspired by advances in medical physics and precision...
Dr
Kalpana Singh
(University of Alberta)
11/01/2017, 10:40
---Canceled Talk---
In the development of high-power, high-frequency gyrotrons,
two major constraints are the thermal loading of the
wall of the waveguide resonator and the potential depression
inhibiting the transport of large electron beam currents. The introduction of a coaxial metal insert in a circular waveguide
resonator reduces the potential depression caused by the
presence of...
Dr
Emmy Sharples
(Helmholtz Zentrum Berlin)
11/01/2017, 11:15
This talk provides an introduction to novel materials for dispersion engineering in an accelerator environment. The focus will me on metamaterials, the unique effects they give rise to and how these can provide interesting responses in accelerators. An overview of existing metamaterials schemes for accelerator applications will be presented, including an in depth discussion on the CSRR...
Prof.
Michael Tobar
(University of Western Australia)
11/01/2017, 11:50
At the University of Western Australia we are investigating novel resonant cavity structures for a variety of applications ranging from tests of fundamental physics, quantum information techniques and applied technologies. After a short introduction, this presentation will focus on our work in designing novel cavities geometries for axion detection. First we will discuss our work on using 3D...
Dr
Nathan Woollett
(LLNL)
11/01/2017, 13:25
As ADMX is looking towards higher frequencies, the reasons to use conventional microwave cavities over other technologies becomes less clear cut. In this talk I will discuss ideas using photonic bandgap structures and meta materials in conjunction with microwave cavities; the benefits which they present and the challenges they pose.
Benjamin Phillips
(University of Washington)
11/01/2017, 14:00
The Electric Tiger experiment is a resonant cavity for the detection of axions in the 4-5 GHz range. The cavity uses a first-of-its-kind detection method – dielectric media placed at regularly spaced intervals within the cavity. Such a search method allows for the construction of a simple tuning mechanism and a wide range of frequencies that can be searched with a single cavity. The tuning and...
Alfred Moretti
(Fermilab)
11/01/2017, 14:35
The talk will cover the application of Ridged waveguide cavities for ADMX research. Designs are given that cover the frequency ragne of 2 GHz to 20 GHz. Their Q's, Coupling Form Factor, and tolerances will be presented. These cavities resonate in the lowest order TE 100 mode because of their long length.
Alfred Moretti
(Fermilab)
11/01/2017, 15:00
Current efforts on studying aluminum superconducting cavities at Fermilab will be presented.
Dr
Harry Themann
(Center for Axion and Precision Physics)
11/01/2017, 15:10
The axion power in a resonant cavity is proportional to B^2V. The radius of cylindrical cavity decreases linearly with increasing frequency thus decreasing the volume as the square of the frequency increase. Attempting to recover the volume, and thus a reasonable axion power, one can increase the length of the cavity. This quickly leads to mode crossings and potential mode localizations due to...
Dr
Larry Phillips
(Jefferson National Lab)
11/01/2017, 16:15
A brief description of SRF cavity R&D activities at JLAB will be presented.
For several decades, Jefferson Lab has been engaged in small sample studies of superconducting film properties using deposition by energetic ion condensation.
Recently a program has been launched using this technique to energetically deposit films on copper cavity substrates for accelerator application, which will...
David Tanner
(University of Florida)
11/01/2017, 16:50
Hybrid cavities, cavities with a layer of superconductor applied on top of the OFHC copper cavity walls, are studied. The goal is to improve the quality factor (Q) of the resonator. The superconductor must have its surface parallel to the external field and must be thinner than the penetration depth and comparable in thickness to the fluxoid spacing in the type II superconductor at the 8 T...
Dr
Won-Jun Jang
(Center for Axion and precision physics research center)
11/01/2017, 17:15
For the successful measurement of cold dark matter, AXION, it is necessary for the development of the high Q superconducting radio frequency (RF) cavity working under high DC magnetic field. For it, type 2 superconducting materials with high critical field and high critical temperature have been suggested. Unlike type 1 superconducting materials, type 2 superconducting materials have the...
Benjamin Brubaker
(Yale University)
12/01/2017, 09:00
I will report on the first results from a new search for axion dark matter using a microwave cavity detector at ~5 GHz frequencies. This detector has achieved near-quantum-limited sensitivity using a dilution refrigerator and Josephson parametric amplifier, and excluded axion-photon-photon couplings a factor of 2.3 above the benchmark KSVZ model in the mass range 23.55 μeV< m <24.0 μeV. These...
Dr
Ohjoon Kwon
(Center for axion and precision physics research @ Institute for Basic Science)
12/01/2017, 09:35
CAPP’s axion searching experiment named as CULTASK (CAPP’s Ultra Low Temperature Axion Search in Korea) adopts P. Sikivies’s axion haloscope that uses strong magnetic field applied high Q factor of microwave cavity. We have started the first CULTASK experiment at 10.3μeV mass region and we demonstrate the progress and prospect. The dilution refrigerator (Bluefors LD 400 series) with 8T...
Prof.
Derek Kimball
(California State University - East Bay)
12/01/2017, 10:40
The nature of dark matter is a key problem in modern physics, and it is important to develop techniques to search for a wide class of dark-matter candidates. Axions, originally introduced to resolve the strong CP problem in Quantum Chromodynamics (QCD), and axion-like particles (ALPs) are strongly motivated dark matter candidates. Nuclear spins interacting with a background axion/ALP field...
Dr
Nicolò Crescini
(Univesity of Padua)
12/01/2017, 11:15
We present a proposal to search for QCD axions with mass in the 200 μeV
range, assuming that they make a dominant component of dark matter. Due
to the axion-electron spin coupling, their effect is equivalent to the application of an oscillating rf field with frequency and amplitude fixed by the axion mass and coupling respectively. This equivalent magnetic field would produce spin flips in a...
Prof.
Andrew Geraci
(University of Nevada Reno)
12/01/2017, 11:50
ARIADNE is a collaborative effort to search for the QCD axion using techniques based on nuclear magnetic resonance. In the experiment, axions or axion-like particles would mediate short-range spin-dependent interactions between a laser-polarized 3He gas and a rotating (unpolarized) tungsten attractor, acting as a tiny, fictitious “magnetic field”. The experiment has the potential to probe...
Ms
Nicole Crisosto
(University of Florida ADMX)
12/01/2017, 13:25
Axions are a promising cold dark matter candidate. Using the conversion of axions to photons in the presence of a magnetic field haloscopes can be employed to detect axions as is done in microwave cavity searches such as ADMX. To search for lighter, low frequency axions in the unexplored sub 100 neV (50 MHz) range a tunable LC circuit has been proposed. Progress in the development of such an...
Mr
Yanjie Qiu
(Quantum Nanoelectronics Laboratory, University of California, Berkeley)
12/01/2017, 14:35
Measurement of weak signals consisting of few microwave photons requires multiple amplification stages for efficient detection by room temperature electronics. However, state-of-the-art commercially available microwave amplifiers add the equivalent of tens of photons of noise, making them insufficient for the amplification of single- or sub-photon signals. Interest in measuring photon-level...
Akash Dixit
(University of Chicago)
12/01/2017, 15:10
The Axion Dark Matter eXperiment (ADMX) aims to detect dark matter axions converting to single photons in a resonant cavity bathed in a uniform magnetic field. A qubit (two level system) operating as a single microwave photon detector is a viable readout system for ADMX and may offer advantages over the quantum limited amplifiers currently used. When weakly coupled to the detection cavity, the...
Dr
SungWoo YOUN
(CAPP/IBS)
12/01/2017, 16:15
Exploring higher frequency regions in axion dark matter searches using microwave cavity detectors requires a smaller size of the cavity as the TM010 frequency scales inversely with the cavity radius. One of the intuitive ways to make a maximal use of a given magnet volume, and thereby to increase the experimental sensitivity, is to bundle multiple cavities together and combine their individual...
Shriram Sadashivajois
(University of Florida)
12/01/2017, 17:25
We use the Pound reflection locking method to tune the cavity. We input
a phase-modulated RF signal to the cavity through a directional coupler.
The RF signal reflected by the cavity is given to a lock in amplifier
using a Zero bias Schottky detector. The output of the lock in amplifier
gives a measure of how far the carrier is off the resonance. This output
is fed to an integrator...
Dr
Richard Bradley
(NRAO NTC)
13/01/2017, 09:00
Details of our work on evaluating commercial phase shifters for cavity impedance matching at cryogenic temperatures are presented. A brief overview of the circuitry is given followed by information on two candidate phase shifters – one surface mount and one packaged. The test and modelling procedures for both bench and cryogenic measurements are outlined. Initial cryogenic measurements...
Daniel Bowring
(Fermilab)
13/01/2017, 09:30
Axion searches above ~1 GHz will employ multiple resonators locked to the same frequency. Fine tuning of individual resonators may be accomplished using thin films of strontium titanate (STO) and related materials, whose dielectic strength can be varied through DC voltage bias. We have developed a method to evaluate these films using coplanar waveguide
resonators. We will discuss the...
Dr
Ian Bailey
(Lancaster University / Cockcroft Institute of Accelerator Science and Technology)
13/01/2017, 09:55
The key difficulty taking cavity axion detectors forward is the rate of coverage of possible axion masses. With metal cavity boundary conditions determining the modal frequencies, you are limited to the physical modes of the cavity having a high form factor. We examine whether artificial modes generated by feedback through high Q resonant filters outside the cavity could form artificial high-Q...
Mr
Ben McAllister
(ARC Centre of Excellence for Engineered Quantum Systems, School of Physics, University of Western Australia)
13/01/2017, 11:00
The Frequency and Quantum Metrology Laboratory at UWA is in the process of constructing a haloscope (the Oscillating Resonant Group Axion converter, or ORGAN) designed initially to search for axions around 110 micro-eV, or 26.6 GHz, with the ultimate goal of performing a wide range search above 20 GHz. The primary motivation for this search is a direct test of the Beck result [1], which claims...
Samantha Lewis
(University of California - Berkeley)
13/01/2017, 11:35
Haloscopic axion searches require the tuning of a TM mode in a microwave cavity. Traditional cavities contain many unwanted modes which can result in mode crossings, ultimately reducing the effective tuning range of a cavity and slowing scan rates. Photonic band gap (PBG) structures have the potential to create resonators without TE modes, allowing for uninterrupted tuning. A tunable PBG...
Dr
Gianpaolo Carosi
(Lawrence Livermore National Laboratory)
13/01/2017, 12:10
Dr
Ian Bailey
(Lancaster University / Cockcroft Institute of Accelerator Science and Technology)