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09 Oct 2025

[ Future Meeting, Tentatively Prof. Yanbao Ma Presenting ]

11 Sep 2025

Attendees:

Agenda:

• Consortium Business
• Upcoming Developments
• AOB

14 Aug 2025 

Attendees: RL, AS, MK, SS, MJ, PB, BL, SD, BZ, AH, NT, JY, IH, GPC, SZ, WL, KO, JL

Agenda:

• Consortium business
  • Welcoming new Consortium members
  • Announcements
    • JY: Shannon and Jared gave a talks/shoutouts about G4CMP in spin qubit community environment, so maybe we'll get some more takers there soon
    • RL: Hopefully TFR pull request comes within about a week.
• Discussion of "Ab initio modeling of nonequilibrium dynamics in superconducting detectors and qubits" (Simon et al., link), led by Alejandro Simon, MIT
• AOB

17 Jul 2025 

Attendees: RM, MK, SS, SQD, AH, BZ, Abhi Nallamalli (Johns Hopkins APL), ÉM, SZ, IH, Osmond Wen, BL, WP, JI, WL, PM, CSW, TC, NT, CL, DS

Agenda:

• Consortium business
  • Welcoming new Consortium members
    • Abhi Nallamalli
    • Osmond Wen (SLAC)
    • Ralf Meyer (Laurentian, Computing+Condensed Matter)
    • David Sadek (UFlorida, SCDMS)
  • Facilities, accounts, etc.
• Updates on tracked film response / QP tracking and diffusion branch (Ryan) (slides)
• AOB

19 Jun 2025 

Attendees: MK, RL, WP, SS, BL, BZ, NT, Wade Lamberson, SZ, PM, GC, TC, JL, ÉM, CL

Agenda:

• Welcoming Wade Lamberson (TAMU)
• Last week was SCMDS Collab meeting so not much recent work/updates
• G4DMC Progress Update for the SuperCDMS Collaboration (Warren Perry)

• G4CMP: Geant4-based Condensed Matter Physics Development for Quantum Information Science

08 May 2025 

Attendees: CSW, RL, SS, ÉM, PB, BL, NT, JL, JY, IH, MK, AP, TC,

Agenda:

• Introductions/Announcements:
  • Mike worked on fixing a bug dealing with high voltage conditions where electrons would get stuck in a loop in mesh during IV process
    • Temporary fix: cut on number of steps the electron can do 
    • IV scattering improvement shown today also fix this problem
  • Mike: Nolan is getting phonon specular reflections nearly fully operational. Emile/Nolan/Mike will coordinate releases over the next few weeks
• Talk on Charge Transport / IV Scattering (Émile Michaud)
• Discussion
• AOB

10 Apr 2025 

Attendees: Ryan, Mike, Gün Süer, Siamak, KC, Micah, Émile, Caitlyn, Nolan, Matthew, Tom, Jared, Eric M, Paul, GPC, Jesse, Birgit, Israel, Guillermo

Agenda:

• Introductions: Gün Süer
• Talk: "Investigations of Nuclear Interactions in Superconducting Quantum Devices" – Micah
• Discussion points others find useful
• Discussion of other interesting APS talks
  • SLAC/UW-Madison MEMS measurements + Selby's MEMS G4CMP modeling talk 
  • Doug P.'s talk on alpha measurements with SC qubits
  • NIST talk on electron beam hitting chiP
  • Others?
• RISQ: any plans for this year? No, but want to do a RISQ-lite where we maybe have a long G4CMP consortium meeting + tutorial.
• AOB

13 Mar 2025 

Attendees: RL, MK, CSW, SS, BZ, CS, BL, JL, NT, TC, ÉM, JY, GC, SZ, EM, IH, MJ, NK

Agenda:

• Question:  Should we create true GitHub "releases" (tar-balls) of G4CMP main-branch tags?
  • May require some development work, especially to get the version number defined outside of git describe .
  • JY: A bit confusing because lots of tags that aren't releases – may solve through documentation or how to make easiest to get most recent one
    • MK: No section on downloading G4CMP in readme file – easy to write a paragraph clarifying 

      Jira
      showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-466

    • Sounds like this is a vote for the tarballs, with good justification
  • SZ: There are three-digit "release tags" and "feature tags".
  • TC: Soft vote for having tarball package – easier for IT team to deal with
    • Want link for someone to click on w/o having to look at github
    • Stack management system? (A&M: EasyBuild – much prefer getting a tarball)
  • CS: appetite for pushing prebuilt package into conda-forge?
    • Mike no like.
    • CS says conda-forge lowers energy barrier for his IT

    • SZ: Conda is discouraged on Canadian clusters.

    • SZ: As a long-term development idea we has envisioned to adopt the SCDMS apptainer release model with computing resource support at SLAC.

  • Conclusions: worth looking into generating these

    Jira
    showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-467

• Introductions (brief): welcome Eric Mascot!
• Discussion of APS March/April Talks
  • G4CMP Consortium Members' Talks/Sessions: MJ, GP, EM, BL, CSW, IH, RL, EY, TC, NK, [Zoey, Aviv, Jaden, Taylor: SLAC]
    • MJ: APR L-19/2
    • BL: Brenden APR L-19/3
    • Jaden@SLAC: charge readout for 526 material, long-term G4CMP relevant
    • To do for Ryan: find other G4CMP folks' talks and put here!
  • Other interesting talks/sessions (link to hastily-made notes document)
  • G4CMP-oriented conference goals?
    • Ryan: learn and compile set of applications for trackedFilmResponse, chat with folks on this
    • CSW: how do we articulate why G4CMP is useful? In what application space is it useful? Goal: help convince holdouts that this is a good tool (at least for particle detection and maybe more?)
  • Would like to organize a dinner to meet y'all in person! Thoughts on the night? Tuesday?
    • Tuesday saw thumbs up
    • MJ: Choose a place with drinks!
  • NK: Standard G4CMP Consortium plug slide for sharing with community – send around to Selby, Noah, Eric, others
• TC: High-level question about G4CMP/Geant4
  • Context: wanting to toggle on/off G4CMP physics for sanity checks
  • Phonon stuff in pure Geant4 toolkit is obsolete
  • Open G4 ticket to remove all of the phonon stuff from G4
• AOB

13 Feb 2025 

Attendees: 

Agenda:

• Introductions
• Talk by Stella Dang (Cornell, FNAL): G4CMP Simulations of a Kinetic Inductance Phonon-Mediated Detector
• AOB

16 Jan 2025  

Attendees: Siamak Sorooshyari, Eric Yelton, Jesse Lutz, Mike Kelsey, Anna Huynh (new!) Jared Yamaoka, John Batarkeh (new?) Brenden Longfellow, Paul Baity, Jake Inman, Émile Michaud, Nolan Tenpas (new!), Tom Carroll, Birgit Zatschler, Philip Mason, Warren Perry

Agenda:

• Introductions
• G4CMP applications, use cases (new folks, especially)
  • What are you interested in modeling?  What do you want from G4CMP?
    • Siamak:  expertise in ML, curious about how that could interact and support G4CMP development (offline chat?)
    • Nolan and Mike:  Phonon specular reflection on curved surfaces, surface mode mockup
    • John and Anna, Wisconsin:  upsets from Co-60 source in fridge; photon-superconductor pair breaking using laser shots on chip to produce phonon bursts
      • Kelsey: Closely related to CDMS HVeV chip:
        • https://journals.aps.org/prd/abstract/10.1103/PhysRevD.105.112006
        • https://www.slac.stanford.edu/exp/cdms/ScienceResults/Publications/2005.14067.pdf
        • https://link.aps.org/doi/10.1103/PhysRevD.105.112006
        • https://www.slac.stanford.edu/exp/cdms/ScienceResults/Theses/azadbakht.pdf
    • Charles Li: Describe QPs as a population with a temperature, rather than single tracking, in bulk superconductors (aluminum crystal block).  Relate thermal conductivity to phonon-QP scattering.  Temperature variation across substrate (use G4Field?)
      • Time stepping vs. single particle transport through static universe.
    • Ryan: feature/RISQTutorial is a good way for new people to get up to speed.  

      Jira
      showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-445

       should be used to track getting it merged onto the main development instead of being a separate feature branch.
  • Are there things G4CMP is doing incorrectly or inaccurately?
• From Kelsey: Small updates and fixes on G4CMP develop branch over the break
  • Make debugging files thread-safe (

    Jira
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    Jira
    showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-439

    Jira
    showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-440

    )
  • Improvements to Phonon_Caustics model (

    Jira
    showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-434

    Jira
    showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-438

    Jira
    showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-437

    )
    • Would like to rename directory to examples/caustics (

      Jira
      showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-443

      )
  • Fix to "Lindhard" (Robinson) NIEL model, from Tom Carroll (

    Jira
    showSummary false server SLAC JIRA columnIds issuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolution columns key,summary,type,created,updated,due,assignee,reporter,priority,status,resolution serverId 1b8dc293-975d-3f2d-b988-18fd9aec1546 key G4CMP-436

    )
• "Propagation velocity measurements of substrate phonon bursts using MKIDs for superconducting circuits",  https://doi.org/10.1063/5.0232368
  • From Jonathan DuBois: "The explanation for the time dynamics they observe doesn't make complete sense to me. In particular, the integrated phonon flux argument for why the see such a strong dependence of the effective propagation velocity on the SNS bias voltage seems to make some strong and not particularly well justified assumptions.  I'm also curious about what appears to be a (relatively) instantaneous effect observed in the data in figure 3 (see below) -- suggesting a photonic or galvanic connection between driving the SNS and the MKID response.
• AOB