On behalf of the NASA Earth Science Division (ESD), the Jet Propulsion Laboratory (JPL) California Institute of Technology, and the NASA Goddard Space Flight Center (GSFC) are studying the prospects for developing a space-qualifiable, atom-interferometry based, gravity gradiometer, hereafter described as a Quantum Gravity Gradiometer (QGG). Such a device consists of two atom interferometers, each configured to measure the local gravity, separated by a fixed baseline. JPL is soliciting information from vendors on the feasibility, performance, and costs of developing prototype space-qualifiable subsystems and components suitable for inclusion in such an instrument. JPL will share all results with other NASA centers. Vendors with experience in developing low size, weight and power, and/or ruggedized components are encouraged to reply even if they lack space experience. The current study sponsored by ESDs Earth Science Technology Office (ESTO), is focusing on a technology demonstration of a QGG on a free-flying satellite in a 4 to 5-year timeframe. The QGG consists of an Atomic Physics Package (APP), a laser and optical subsystem, and associated electronics, control, data handling, and thermal subsystems. The APP includes the key physics sub-systems for atom interferometry including a vacuum chamber, atomic sources, atom cooling, atom transport (if needed), state preparation, atom detection and magnetic shielding. The laser system consists of lasers for atom trapping, atom cooling, atom transport (if needed), atom interferometry and detection; along with associated optics, opto-mechanical assemblies, fiber optics, and modulators. Lasers are stabilized relative to atomic transitions in Cs and Rb. One possible QGG configuration would include two independent atom sources and associated cooling optics separated by the baseline; alternatively, a single atom source could be employed to produce a single initial sample of atoms which is then split and utilized as two independent interferometers separated by a baseline. Based on current JPL studies, options that employ laser cooling alone (Option 1) are being considered along with systems that utilize ultra-cold atoms produced via evaporative cooling or other means (Option 2). In the longer term, NASA is interested in developing a QGG device with performance levels dramatically beyond the current state-of-the-art. Such a device will be required if this technology is to contribute to expected future gravity-mapping missions. Enhancements might include larger atom numbers, colder temperatures, longer interaction times, and longer baselines. If possible, it would be useful for vendors to comment on the prospects for their technology to contribute to a future enhanced mission. Vendors could propose delivery of entire subsystems, individual components, or an entire QGG system, and are welcome to submit information on multiple components and subsystems. JPL will partner with vendors on space qualification aspects, as needed. JPL asks that you identify your proposed technological approach and comment on its principal performance-cost relationships. Your responses will also help NASA ESD determine the interest in providing this type of effort and allow us to refine our requirements and possible contract implementation approach. Respondents are free to choose atomic species (Rb or Cs), cooling configurations (laser cooling, evaporative cooling, etc.), and atom interferometer type (Bragg or Raman) in order to best achieve the performance goals. A brief discussion of these choices should be included. JPL envisions that the next steps in our study will include focused, funded, vendor evaluations of some of the technologies described in responses to this RFI. Other centers may also be interested in pursuing similar studies. The targeted performance goals for this device are given in Table 1 - Targeted Performance Goals for Space-based QGG, attached. Please answer the following Questionnaire regarding the development of a space-qualifiable (TRL6) Cold Atom Gravity Gradiometer: 1.0 General Questions 1.1 Is your company interested in working with NASA JPL and/or NASA GSFC to develop components for a space qualifiable (TRL6) Cold Atom Gravity Gradiometer? 1.2 Does your company have previous experience related to generating space- qualified devices? 1.3 Are you proposing a component, subsystem, or entire QGG system? If proposing an entire QGG system, please present your basis for estimating the systems performance. 2.0 Performance Estimates 2.1 Will your device meet the target performance goals listed in Table 1? Please complete Table 1 with relevant parameters to the extent possible. 2.2 What are the technical difficulties, if any, that may preclude you from meeting any of the specified targeted capabilities? 2.3 Can any of the targeted performance goals be significantly exceeded for a relatively minor increased cost? Please indicate which goals could be exceeded and what the expected increase in costs would be. 3.0 Cost Estimates 3.1 What is your Rough Order of Magnitude (ROM) estimate of the overall cost of delivering one prototype of a proposed device, suitable for thermal, and vibration testing at NASA or equivalent facilities. 3.2 What is your ROM estimate of the overall cost of delivering a second prototype? 3.3 Does your company have the capability to perform vibration and/or thermal testing on site? If so, what would be the ROM cost of such a service? 3.4 What do you see as the major cost drivers for this item? 3.5 Does your company produce a product that is a commercial equivalent to the proposed device, and that could be used in preliminary system-level tests of a QGG? If so, what is the cost of this component? 4.0 Schedule Estimates 4.1 What is your ROM estimate for a relative schedule that will lead to delivery and acceptance by NASA ESTO of one prototype? 4.2 If applicable what would be the ROM estimate for a schedule for your company to provide vibration and/or thermal testing on site? 5.0 Additional Comments Please feel free to provide additional comments or recommendations. Questions and Submission of Responses In order to maximize the return on information for NASA from all participants, our answers to any specific questions raised as a result of this questionnaire will be sent to all parties participating in this RFI, and NASA will keep the identity of the questioner confidential. Your response to the full request (RFI) is also confidential. Technical questions should be sent directly to Robert Thompson via email to
[email protected] Business questions should be sent directly to Kirk Bilby via email to
[email protected] Response Deadline Please provide the requested information, including the Attachment 1 - Contact Information Form, on or before February 1, 2023 via email to both of the above contacts. Your participation and response is greatly appreciated. Your response to the full request (RFI) is also confidential and does not in any way obligate JPL or the government to purchase any product or services. DISCLAIMER: The requested information is for preliminary planning purposes only and does not constitute a commitment, implied or otherwise, that JPL will solicit you for such procurement in the future. Neither JPL nor the Government will be responsible for any costs incurred by you in furnishing this information. Prospective subcontractors are advised that any information provided shall be deemed to be furnished with unlimited rights to JPL, with JPL assuming no liability for the disclosure, use or reproduction of such data. This document has been reviewed and determined not to contain export controlled technical data