SBIR-STTR Award

Carbon nanotubes (CNT) are the darkest material known to man and are an enabling technology for scientific instrumentation of interest to NASA. The chemical vapor deposition (CVD) of carbon nanotubes directly onto high quality mirrors for diffraction suppression and stray light control is critical for use reflective nulling coronagraphs. The development of an integrated optical stack for these applications is new technology that has never been demonstrated. Sub-micron controlled patterning of carbon nanotubes for extreme stray light control must be made to be compatible with high reflectivity coatings without degrading the near diffraction limited surface figure on the underlying substrate. The entire optical stack; substrate, reflective coating and carbon nanotube forest, must be able to withstand high power laser pulses without damage and be robust to launch environments. This is critical to missions that require extreme nulling of bright sources adjacent to dim companions. The second component required for a nulling coronagraph is a sharp edge low scatter Lyot stop to block light. Etched silicon has been used as an entrance slit for instruments and have been successfully fabricated and coated with ultra dark nanotubes by proposal team members. The Principal Investigator at Lamba Consulting is a recognized expert in the development of carbon nanotubes, novel mirror substrates and coating technologies for space flight applications and has formulated a plan for fabricating and qualifying demonstration optics including for both a reflected apodization mirror and Lyot stop selectively coated with carbon nanotubes.

Potential NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) Stray-light and diffraction suppression is critical to NASA instrumentation because it improves signal to noise and observational efficiency in high contrast regions present in Earth, solar and coronagraphic applications. The PI and Lambda Consulting have delivered a large variety of instrument components including, baffles, stops, tubes and beam dumps. Development of a process compatible with reflective coatings and high quality optics for this SBIR, will enable an entirely new class of components and instrumentation for scientific observations. NASA requires calibrators for all manner of instruments to allow scientific data to be of the highest accuracy. On-mirror diffraction suppression is enabling for e-LISA as the telescope is used in duplex and requires extreme suppression of the the high power transmitted beam. This is also a challenge in Laser Communications and of great interest to NASA that will be addressed by this SBIR. Carbon nanotubes have the highest emissivity ever measured and are nearly ideal in this respect. We expect that further enhancement of the robustness of carbon nanotube coatings demonstrated in this SBIR will result in the use of this technology on more NASA instruments. The PI has built and tested carbon nanotube absorber thermal detectors with superconducting transition edge detectors; a modified CVD process will make the use of carbon nanotube absorbers compatible with more detector technologies.

Potential NON-NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) Optimization of the optical stack outlined in this SBIR proposal addresses a host of challenges that have created a barrier to the use of carbon nanotubes in commercial stray light control applications. Phase I of this SBIR will confront many of these challenges and a successful Phase II will constitute closure of many of the issues that have been problematic to commercialization. Laser communications and autonomous vehicle control can benefit from stray light control for optical systems used in duplex; this is a direct application of this technology. Beyond the need for on-board calibration systems, laboratories across the world would benefit from a near zero reflectance calibration standard for spectrophotometers and other scientific and military equipment. Lamba Consulting is actively investigating the use of alternate adhesion materials to make nanotube formulations more robust for these applications. The use of gold black on thermopile detectors for scientific and military instruments has been problematic due to the fragility of the coating and difficulty of patterning. We are actively seeking industry partners to develop thermopile arrays. The PI has been working with well-known artists Frederik de Wilde and Diemut Stebe to create black art using carbon nanotubes. Representatives of Louis Vuitton, Tesla and Swatch have been in communication and await further adhesion optimization to utilize carbon nanotubes in a variety of design and fashion applications

Technology Taxonomy Mapping:
(NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.) Filtering Mirrors Multispectral/Hyperspectral Nanomaterials Optical Radiometric

In Phase I we demonstrated each aspect required for design and fabrication of Lyot Stops and Apodization Masks for use in a coronagraphic instrument and delivered working components to collaborators at NASA and the Space Telescope Science Institute for evaluation. The technical achievements included: 1) first high quality mirror with carbon nanotubes 2) First nanotubes grown on metallic coatings 3) Dark patterned carbon nanotubes with micron-scaled features. During Phase II we will work with the NASA and STScI collaborators to determine how to improve these components and deliver second generation components to extend the performance of the STScI test bed in support of implementation on future NASA missions such as HABEX or UVOIRS. In addition we will work with NASA collaborators to design and fabricate carbon nanotube coated Lyot Stops for the Visible Nulling Coronagraph (VNC) test bed, also of key importance to the decadal missions referenced above. Lastly, we plan to collaborate with the LISA telescope team at NASA GSFC to design and fabricate a carbon nanotube apodization mask on a powered secondary mirror that could be used in single crystal silicon telescope as a pathfinder for LISA. One of the technical goals of Phase II are to pattern more complex Lyot Stop geometries while maintaining geometrical accuracy through the nanotube growth process. Further optimization of the apodization masks for coronagrahic use include: 1) increasing the metallic coating reflectance to near ideal 2) optimization of the nanotube darkness on the metallic coatings 3) greyscale patterning of carbon nanotubes and medium reflectance coatings on the mirrors to achieve enhanced diffraction suppression. For the LISA telescope diffraction spoiler application we will demonstrate patterning and growth of carbon nanotubes at the micron scale which when combined with metallic nanostructures can provide enhanced field suppression; another enabling technology to NASA missions.

Potential NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) Stray-light and diffraction suppression is critical to NASA instrumentation because it improves signal to noise and observational efficiency in high contrast regions present in Earth, solar and coronagraphic applications. The PI and ANP/LC have delivered a large variety of instrument components including, baffles, stops, tubes and beam dumps. Development of a process compatible with reflective coatings and high quality optics for this SBIR, will enable an entirely new class of components and instrumentation for scientific observations. NASA requires calibrators for all manner of instruments to allow scientific data to be of the highest accuracy. On-mirror diffraction suppression is enabling for e-LISA as the telescope is used in duplex and requires extreme suppression of the the high power transmitted beam. This is also a challenge in Laser Communications and of great interest to NASA that will be addressed by this SBIR. Carbon nanotubes have the highest emissivity ever measured and arenearly ideal in this respect. We expect that further enhancement of the rob ustness of carbon nanotube coatings demonstrated in this SBIR will result in the use of this technology on more NASA instruments. The PI has built and tested carbon nanotube absorber thermal detectors with superconducting transition edge detectors; a modified CVD process will make the use of carbon nanotube absorbers compatible with more detector technologies.



Potential NON-NASA Commercial Applications:
:
(Limit 1500 characters, approximately 150 words) During Phase I of this SBIR we developed coatings and chemical vapor deposition processes compatible with high surface quality single crystal silicon mirrors. Phase II will continue optimization of these optical components for NASA and commercial use. We believe that this technology can be applied to autonomous vehicle imaging where stringent stray light control is required to enable robust operation in challenging lighting conditions. In addition, success during Phase I has initiated collaborative efforts with the Swatch group, who are interested in patterning nanotubes on gold or silver coated substrates for high end watches. Advanced Nanophotonics, Inc. is also collaborating with the technical arm of Universal Studios to deliver samples of ultradark nanotube coatings for use in special effects.

Technology Taxonomy Mapping:
(NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.) Image Capture (Stills/Motion) Infrared Lasers (Communication) Mirrors Nanomaterials Optical Radiometric Spacecraft Instrumentation & Astrionics (see also Communications; Control & Monitoring; Information Systems) Transmitters/Receivers Visible