Ultra-High-Frequency GWs: A Theory and Technology Roadmap

12 Oct 2021, 14:00 → 15 Oct 2021, 20:00 Europe/Zurich

Zoom only (CERN)

Nancy Aggarwal, Valerie Domcke (CERN), Francesco Muia (University of Cambridge), Fernando Quevedo (University of Cambridge), Andreas Ringwald (Deutsches Elektronen-Synchrotron DESY), Jessica Steinlechner, Sebastian Steinlechner

This workshop is part of the Ultra-High-Frequency Gravitational Waves initiative (see the website of our initiative) and comes after a first meeting held at ICTP in Trieste in 2019 (see the website of the first workshop) that led to a review paper on the subject.

The aim of this meeting is to foster the technology development that is necessary to get to ultra-high-frequency gravitational wave detection. In particular, we will discuss

• the science case for UHF-GW searches
• new detector concepts
• feasibility studies and construction of prototypes for proposed detector concepts
• coordinating an international effort to support collaborations working on UHF-GW detectors

The workshop will combine theoretical developments regarding GW sources in different parts of the ultra-high-frequency band with experimental concepts aiming at probing them.

Each day we will have a discussion session with the aim of setting up working groups around one or more detector concepts and/or theoretical aspects of sources, which will be encouraged to continue their work after the end of the workshop, hopefully contributing to the technology development that is needed to make concrete progress in the field.

If you would like to contribute a talk, please contact the organizers.

We warmly invite all participants to join our mattermost discussion channel. To join for the first time, please use this invitation link. For instructions and help debugging, see here.

Tuesday, 12 October

14:00 → 14:15 Opening

Convener: Prof. Mike Cruise (University of Birmingham)

Recording

14:00 Opening

Speaker: Prof. Mike Cruise (University of Birmingham)

cruise

Mike Cruise.mp4

14:15 → 15:15 Experimental Concepts: Below the MHz

Convener: Francesco Muia

14:15 Detecting high-frequency gravitational waves with optically levitated nanoparticles

Speaker: George Winstone (Northwestern University)

Recording

UHFGW .pdf

winstone.mp4

14:45 Quantum Frequency Interferometry: with applications ranging from gravitational wave detection to dark matter searches

Speaker: Ivette Fuentes (University of Nottingham)

fuentes.mp4

FuentesUHF-GW2021.pdf

Recording

15:15 → 15:45 Discussion: pre-recorded contributed talks

Tabletop detectors

15:15 Gravitational Wave Gastronomy

The symmetry breaking of grand unified gauge groups in the early universe often leaves behind relic topological defects such as cosmic strings, domain walls, or monopoles. For some symmetry breaking chains, hybrid defects can form where cosmic strings attach to domain walls or monopoles attach to strings. In general, such hybrid defects are unstable and can leave behind unique gravitational wave fingerprints. In this talk, I will discuss the gravitational wave spectrum from 1) the destruction of a cosmic string network by the nucleation of monopoles which cut up and eat’ the strings, 2) the collapse and decay of a monopole-string network by strings that ‘eat’ the monopoles, 3) the destruction of a domain wall network by the nucleation of string-bounded holes on the wall that expand andeat’ the wall, and 4) the collapse and decay of a string-bounded wall network by walls that eat’ the strings, with a particular focus on the latter for this talk. We call the gravitational wave signals produced from theeating’ of one topological defect by another “gravitational wave gastronomy”. We find that the gravitational wave gastronomy signals considered yield unique spectra, typically at ultra high frequencies, that can be used to narrow down the SO(10) symmetry breaking chain to the Standard Model and the scales of symmetry breaking associated with the consumed topological defects.

Speaker: David Dunsky (UC Berkeley)

GW_Gastronomy.mp4

GW_Gastronomy.pdf

Recording

15:15 Gravitomagnetic resonance and gravitational waves

Gravitational waves are usually described in terms of a
transverse and traceless (TT) tensor, which allows to introduce the so-called TT coordinates. However, another possible approach is based on the use of a Fermi coordinates system, defined in the vicinity of the world-line of an observer arbitrarily moving in spacetime. In particular, Fermi coordinates have a direct operational meaning, since they are the coordinates an observer would use to perform space and time measurements; indeed, using these coordinates the metric tensor contains (up to the required approximation level) only quantities that are invariant under coordinate transformations internal to the reference frame. Using this approach it is simple to emphasise that what an observer measures depends both on the background field where he is moving and, also, on his kind of motion. This is quite similar to what happens when we study classical mechanics in non inertial frames: inertial forces appear, depending on the peculiar motion of the frame with respect to an inertial one. We show that using Fermi coordinates the effects of a plane gravitational wave can be described by gravitoelectromagnetic fields: in other words, the wave field is equivalent to the action of a gravitoelectric and a gravitomagnetic field, that are transverse to the propagation direction and orthogonal to each other. In particular, the gravito-magnetic field acts on spinning particles and we show that, due to the action of the gravitational wave field a gravitomagnetic resonance may appear. We give both a classical and a quantum description of this phenomenon and suggest that it can be used as the basis for a new type of
gravitational wave detectors.

Speaker: Matteo Luca Ruggiero (Politecnico di Torino)

Recording

ruggiero_ML.mp4

ruggiero_ML.pdf

15:15 GW experiments for dark matter direct detection

Speaker: Yue Zhao (University of Utah)

GW-DPDM.mp4

GW-DPDM - O3 - short.pdf

Recording

15:15 Resonant Electromagnetic Gravitational Wave Detectors

Speaker: Nicolas Herman (University of Namur)

Recording

Slides.pdf

VIDEO.MOV

15:15 Ultra-high frequency gravitational waves from alpha-attractor models of inflation

We consider primordial gravitational waves induced by large density perturbations generated by inflation in the very early universe. Cosmological alpha-attractors stand out as particularly compelling models to describe inflation, naturally meeting tight observational bounds from cosmic microwave background (CMB) experiments. We investigate alpha-attractor potentials in presence of an inflection point. The curvature perturbation is enhanced at high frequencies, which can lead to primordial black holes production and second-order gravitational waves. Consistency with the current CMB measurements implies that PBHs can only be produced with masses smaller than 10^8 g and are accompanied by ultra-high frequency gravitational waves, with a peak expected to be at frequencies of order 1MHz or above.

Speaker: Laura Iacconi (Institute of Cosmology and Gravitation (University of Portsmouth))

Iacconi_GW_workshop.mp4

Iacconi_UHF-GW_workshop.pdf

Recording

15:15 Ultra-High-Frequency Gravitational Waves from Oscillons

Speaker: Evangelos Sfakianakis (IFAE)

Recording

Sfakianakis_oscillons.mp4

Sfakianakis_UHFGW_2021.pdf

15:40 recording

contributed_talks.mp4

Recording

15:45 → 16:00 coffee break

16:00 → 17:00 Theory: Below the MHz

Convener: Dr Ornella Juliana Piccinni

16:00 Searching for ultra-light axions with high-frequency gravitational waves

Speaker: Masha Baryakhtar (PI - Perimeter Institute for Theoretical Physics (CA))

baryakhtrar.mp4

HFGWs_superradiance.pdf

Recording

16:30 Gravitational waves of exotic compact object mergers

Speaker: Eugene Lim (King's College London)

lim.mp4

Recording

UHF_GW_2021_talk.pdf

17:00 → 17:15 coffee break

17:15 → 18:15 Discussion: Tabletop scale experiments

Tabletop detectors

Convener: Nancy Aggarwal (Northwestern University)

17:15 discussion: table-top experiments

discussion table-top experiments

Recording

Wednesday, 13 October

13:30 → 14:00 Discussion: on talks of previous day

Tabletop detectors

13:30 discussion on talks of previous day

discussion_wed_1.mp4

Recording

14:00 → 15:00 Theory: Above the GHz

Convener: Emanuela Dimastrogiovanni (The University of New South Wales)

14:00 Probing sub-solar PBHs with UHF-GWs

Speaker: Sébastien Clesse (Université Libre de Bruxelles (ULB))

CLESSE_HFGW_workshop.pdf

clesse.mp4

Recording

14:30 Cosmic Gravitational Microwave Background

Speaker: Carlos Tamarit (Technische Universität München)

CGMB.pdf

Recording

tamarit.mp4

15:00 → 15:15 coffee break

15:15 → 16:45 Experimental Concepts: Above the GHz

Convener: Giancarlo Cella (INFN - National Institute for Nuclear Physics)

15:15 Magnetic Conversion Detectors

Speaker: Dr Aldo Ejilli (University of Cardiff)

Aldo_Ejlli_13_10_2021.pdf

eijlli.mp4

Recording

15:45 ALPS II and UHF-GWs

Speaker: Axel Lindner (DESY)

ALPS-DESY.pdf

lindner.mp4

Recording

16:15 Enhanced magnetic conversion

Speaker: R. Clive Woods (University of South Alabama)

LiBakerDetector - Copy.pdf

LiBakerDetector - Copy.ppt

Recording

woods.mp4

16:45 → 17:00 coffee break

17:00 → 18:00 Discussion: Theory

Tabletop detectors

Convener: Valerie Domcke (CERN)

17:00 discussion theory

discussion_wed_2.mp4

Recording

Thursday, 14 October

10:00 → 10:30 Discussion: on talks of previous day

Tabletop detectors

10:00 discussion on talks of previous day

discussion_thursday_1.mp4

Recording

10:30 → 11:30 Theory: Further ideas

Convener: Subodh Patil (University of Leiden (NL))

10:30 Early Universe Sources

Speaker: Prof. Richard Easther (The University of Auckland)

easther.mp4

Recording

uhf-gw.pdf

11:00 UHF GWs from a spinning axion

Speaker: Geraldine Servant (Deutsches Elektronen-Synchrotron (DE))

high-frequency-14-10-21.pdf

Recording

servant.mp4

11:30 → 12:00 coffee break

12:00 → 13:30 Experimental Concepts: Further ideas

Convener: Ivette Fuentes (University of Nottingham)

12:00 UHF-GW solid state detector proposal

Speaker: Prof. Juan Garcia-Bellido Capdevila (Universidad Autonoma Madrid)

garcia-bellido.mp4

Recording

UHF-GW-SolidStateDetector-JGB-14Oct21.pdf

12:30 GWs and mesoscopic quantum systems

Speaker: Prof. Francesco Sorge (INFN Napoli)

Recording

sorge.mp4

UHF_GW_GRAPHENE.pdf

13:00 Cosmological detectors of UHF GWs

Speaker: Camilo Garcia Cely (Deutsches Elektronen-Synchrotron DESY)

garcia-cely.mp4

Recording

TalkGarciaCely.pdf

13:30 → 14:00 coffee break

14:00 → 15:00 Discussion: Experimental Concepts

Tabletop detectors

Convener: Andreas Ringwald (Deutsches Elektronen-Synchrotron DESY)

14:00 discussion large-scale experiments

discussion_thursday_2.mp4

Recording

Friday, 15 October

10:00 → 10:30 Discussion: on talks of previous day

Tabletop detectors

10:00 discussion on talks of previous day

discussion_friday_1.mp4

Recording

10:30 → 12:00 Mixed Session: Between MHz and GHz

Convener: Camilo Garcia Cely (Deutsches Elektronen-Synchrotron DESY)

10:30 Bulk acoustic wave detectors

Speaker: Prof. Michael Tobar (University of Western Australia)

Recording

tobar.mp4

UHF-GW workshop Tobar.pdf

11:00 Magnon limits on high frequency gravitational waves

Speaker: Prof. Jiro Soda (Kobe University)

HFGW2021.pdf

Recording

soda.mp4

11:30 NEMO

Speaker: Dr Vaishali Adya (Australian National University)

adya.mp4

NEMO_Adya_UHV_upload.pdf

Recording

12:00 → 12:30 coffee break

12:30 → 13:30 Experimental Concepts: Microwave cavities

Convener: Francesco Sorge (INFN Napoli)

12:30 Microwave cavities

Speaker: Dr Diego Blas (Institut de Fisica d'Altes Energies)

21UHF_GWs_Blas.pdf

blas.mp4

Recording

13:00 Microwave Cavities

Speaker: Dr Raffaele Tito d'Agnolo (IPhT Saclay)

dagnolo.mp4

GW_Cavity.pdf

Recording

13:30 → 13:45 coffee break

13:45 → 14:45 Discussion: UHF GW initiative / living review

Tabletop detectors

Convener: Mike Cruise (University of Birmingham)

13:45 discussion: next steps for UHF GW initiative

discussion_friday_2.mp4

RecapSlides.pdf

Recording