PROGRAM OBJECTIVE AND DESCRIPTION

The SUNSPOT program aims to develop coherent sources of vacuum ultraviolet (VUV) radiation for clock-grade spectroscopy of the recently discovered thorium (229mTh) nuclear isomeric transition. It is anticipated that the coherent optical sources developed during this program will enable high-resolution spectroscopy of the thorium clock transition; quantification of clock-related drifts, inhomogeneities, and spectral shifts; and an assessment of the potential performance of a thorium-based solid-state optical clock.

The combination of ultracoherent optical sources and optical frequency combs has enabled the development of optical clocks with demonstrated precision currently in the 10-20 range – orders of magnitude beyond the performance of microwave-domain clocks. In addition to providing resilience and operability in GPS-denied conditions, the superior performance of optical clocks could also support a burgeoning set of commercial applications that require increased connectivity, high bandwidth, low latency, and beyond-GPS timing precision. However, despite extensive efforts to enhance their technology readiness level (TRL), the most stable and accurate optical clocks still have significantly inferior environmental resilience, system-level integration, and size, weight, and power (SWaP) requirements than do microwave-domain clock technologies.

An alternate path to resilient, low-SWaP optical-domain timekeeping may be offered by the recent discovery of an optically addressable nuclear isomeric transition in thorium-229 (229mTh) at the VUV wavelength of 148.382 nm. Preliminary spectroscopic measurements and theoretical modeling of an all-solid-state nuclear clock suggest fractional clock instability in the 10-16-10-17 range. However, precision optical spectroscopy of this nuclear transition is an essential next step to rigorously assess the viability and potential performance of a thorium-based nuclear clock. A key enabling technology for such spectroscopic studies, i.e., a high-coherence VUV optical source at the thorium wavelength, does not currently exist. This solicitation seeks to fill this technological void by developing such a coherent VUV optical source.

EVENT PARTICIPATION

Eligibility

DARPA is hosting this Proposers Day to: (1) promote teaming arrangements between researchers; (2) provide potential proposers with information on whether and how they might respond to the Government’s research and development solicitations; and (3) increase efficiency in proposal preparation and evaluation. Therefore, this Proposers Day is only open to registered potential proposers (i.e., the events are closed to the general public and media). For this particular program, Proposers Day registration is open to potential proposers who are U.S. citizens, U.S. permanent residents, and foreign nationals.

All registrants who are not U.S. citizens must complete and submit either a DARPA Form 60 (U.S. Permanent Resident and Foreign National Visit Request – e.g., industry or academia) or an Official Visit Request (foreign government personnel, only) through their country’s embassy based in Washington, D.C., no later than 12:00 PM ET on January 31, 2025. Form 60 submission instructions are provided in the registration confirmation email. Contact your embassy staff for assistance in submitting the Official Visit Request.

Registration

There is no registration fee for the Proposers Day webcast. Registration closes on January 31, 2025 at 12:00 PM ET, or when capacity is reached, whichever comes first.

Advance registration is required. NOTE: All persons wishing to attend the webcast must register (whether viewing alone or as part of a group).

Registrants in excess of the maximum capacity limitations (250 individuals) may be added to a waitlist. Individuals who are unable to register because the deadline has occurred may request to be added to the waitlist. If slots become available due to cancellations, the slots may be filled on a first-come, first-served basis from the waitlist.

TEAMING OPPORTUNITIES

TEAMING

DARPA highly encourages teaming before proposal submission and will facilitate the formation of teams with the necessary expertise. Potential proposers may choose to participate in either, none, or both of the following options:

Attendee List (limited distribution): Participant contact information (name, organization, email address) will be distributed to all other SUNSPOT Proposers Day attendees. The registration website will ask registrants to indicate whether they approve distribution of their contact information.
Proposer Profile List (limited distribution): Interested parties will submit a one-page profile consisting of their contact information (i.e., name, organization, email, telephone number, mailing address, and, if applicable, organization website), a brief description of their technical competencies, and, if applicable, their desired expertise from other teams/organizations. All profiles must be emailed to SUNSPOT@darpa.mil no later than 4:00 PM ET on February 10, 2025. Following the deadline, the consolidated teaming profiles will be sent via email to the proposers who submitted a valid profile. Specific content, communications, networking, and team formation are the sole responsibility of the participants. Neither DARPA nor the Department of Defense (DoD) endorses the information and organizations contained in the consolidated teaming profile document, nor does DARPA or DoD exercise any responsibility for improper dissemination of the teaming profiles.

LIGHTNING TALKS

Attendees may be afforded the opportunity to give a Lightning Talk (a 3-minute oral presentation) during the webcast outlining their interests and capabilities. The purpose of these presentations is to facilitate teaming discussions among the attendees. Upon registering, attendees may indicate if they would like to give a Lightning Talk. Due to limited availability, DARPA will accept submissions on a first-come, first-served basis and does not guarantee an attendee’s requests to brief will be fulfilled. Submitted briefings are limited to a single, PDF-format slide, which should be appropriate for public release, as they will be shared with the session via webcast. The slide must be submitted to SUNSPOT@darpa.mil by 4:00 PM ET on February 4, 2025. DARPA will contact submitters upon receipt of their slide with additional guidance for the webcast.

SIDEBAR MEETINGS

There will be an opportunity to meet individually with the Program Manager, Dr. Mukund Vengalattore. Eight-minute, individual, virtual meetings will be held during Proposers Day between 2:15 PM and 4:15 PM ET. Please request an individual/team (limited to four (4) people per team) session via the registration website. Requests must be received no later than the registration deadline date. Individual meetings will be scheduled on a first-come, first-served, and space-available basis and limited to two (2) people per institution.

From 2:15 PM to 3:15 PM ET, the DARPA Contracts Management Office (CMO) will be hosting a separate meeting targeting proposer contracting personnel to answer any questions and provide additional information on how to propose to the forthcoming solicitation.

AGENDA

Click the button below to see the tentative agenda.

February 7, 2025

Webcast - ZoomGov

Scroll down for more information