RIT has embarked on the Cosmic Radiation Damaged Image Repair project (CRDIR) involving Dr. Donald Pettit, NASA Astronaut & International Space Station astrophotographer. This project is being conducted by graduate and undergraduate student researchers under the guidance of Dr. Donald Figer, Director of CfD.
Students will have a unique opportunity to communicate with an active American astronaut in the process of solving a significant image processing issue. The scientific process these students will follow toward a solution will provide valuable experience that these students will carry with them in their professional lives.
RIT will be providing a sophisticated “image enhancement” software program which specifically addresses degraded images taken by astronauts “on orbit”, extending the useful lives of cameras, and in many cases making unacceptable “noisy” images visually acceptable.
Inter-Pixel Capacitance (IPC) is a mechanism for deterministic electronic cross talk that results from coupling fields between adjacent pixels as a signal is collected and stored. Simulation of small arrays from first principles using software which simultaneously solves Poisson's equation and the Drift Diffusion equations allows for characterization of this coupling across a broad range of design parameters as well as across various environment parameters. Due to the deterministic nature of this cross-talk characterization results in correction.
This project is currently working on characterization of HgCdTe arrays hybridized using indium bumps to H2RG readout circuits akin to those to be used in the James Webb Space Telescope's (JWST) NIRcam. Successful characterization across environment parameters will result in an increase in final image quality from JWST's NIRcam and any device using a similar detector while also introducing new design considerations for future generations of sensor.
RIT is developing a silicon MOSFET CMOS imager to detect terahertz (THz) frequencies in a collaboration with the Center for Emerging and Innovative Sciences (CEIS) at the University of Rochester and Exelis Geospatial Systems. Creating an asymmetrical design within the FETs, increases the THz response. The current device being tested was designed with 15 individual test transistors with varying design dimensions and antennas along with an array of transistors for an imager. These test structures are being evaluated at RIT to determine the best design for terahertz detection for future imager designs. An advantage of this detector technology is that these MOSFETs will not have to be cooled to extreme temperatures like microbolometers. This project will advance knowledge of the detection mechanism, lead to the creation of an integrated imaging system, and has many different applications.
THz frequencies have been largely unexplored due to high absorption within water, however there has been an increase in interest with the rise in high-altitude and space-based telescopes. Emission lines in spectra within the THz regime exhibit cool molecular gas which traces protoplanetary disks and star formation rates within galaxies. This technology will also have other applications within the medical and security fields because of the non ionizing, non-harmful nature of THz radiation.
The primary objective of this project is the realization of an integrated photonics platform compatible with photon-ion entanglement. The platform will consist of photon sources and entangling circuits that interface with the visible/UV wavelengths of ion (such as Yb+, Ca+, Be+, Mg+, Sr+, Ba+, Zn+, Hg+ and Cd+) transitions. The challenge with realizing such a platform is that integrated photonic chips are not well developed at visible wavelengths because of the traditional focus on telecom wavelength compatibility.
RIT is developing a platform that does operate at short wavelengths by using Aluminum Nitride (AlN), which is a large bandgap semiconductor that is transparent to the deep-UV In parallel, we are leveraging our successes in quantum integrated photonics in telecom-compatible platforms, particularly silicon photonics. This will allow rapid validation of high performance photon sources, entanglement circuits and quantum sensors. These circuits will then be transitioned to the new visible/UV platform, or interfaced with ions directly by using frequency conversion.
The world demand for, and consumption of, energy is dramatically increasing, with an increasing demand for renewable non-fossil based sources of electricity. As well, there is an ever growing demand for increased power and sophistication in the satellite systems orbiting our planet, driven by our increasing reliance on high speed communication and data links. The conversion of light from the sun into electrical energy, using photovoltaics, is one avenue that can be explored to meet these challenges both on the earth and in space. The mission of our research group is to accelerate scientific breakthroughs in the discovery of nanoscale materials and structures that will advance the frontier of the conversion of light to electricity. Our focus is new materials synthesis, device modeling and simulation, solar cell device fabrication and demonstrating proof-of-principle of devices that will deliver a major boost to the world’s pursuit of innovative and transformative energy conversion products. Our team’s expertise lies in vapor phase epitaxy (VPE) of III-V photovoltaic and photonic devices and nanostructures, bandgap engineering using epitaxial nanostructures, novel photovoltaic devices such as the intermediate band solar cell, photovoltaic characterization, simulation, design and testing.
SPHEREx is a planned NASA small explorer which will perform an all-sky spectral survey of the in near-infrared bands. SPHEREx was recently selected for a NASA Phase A study, work is required to refine the instrument concept before a down-select occurs in mid-2016. This program is refining details of the instrument, observation strategy, and data analysis plans to create visual materials to help NASA and the public understand the experiment and expected science output.
The growth of various nanostructures, including nanowires and nanofins, by metal-organic chemical vapor deposition (MOCVD) is investigated through a unique crystal synthesis process known as selective area epitaxy (SAE). The SAE method relies on an oxide template with predefined windows that specify the location of preferential epitaxial atomic assembly. Growth rate enhancement, as defined by the oxide template, allows for the controlled epitaxy of arrays of vertical, III-V compound semiconductor nanostructures without the use of foreign catalytic or seeding agents. Based on the SAE technique, the EINS lab has demonstrated growth of InAs, InGaAs, GaAs, GaAsP, and GaP nanowire and nanofin arrays on Si substrates with 100% yield over large, wafer-scale areas. Our current projects aim to understand the growth kinetics of III-V nanosystems interfaced with Si and 2-dimensional nanomaterials such as graphene and monolayer transition metal dichalcogenides; to characterize the novel material properties offered by these hybrid nanosystems; and to demonstrate their utility in innovative photovoltaics and optoelectronics solutions.
RIT’s Photonics and Optics Workforce Education Research group (POWER) unites STEM education research with workforce development in order to investigate the critical scientific and mathematical knowledge, hands-on abilities, communication skills, and other essential competencies for jobs in photonics. The group is conducting an on-going study of optical technician and engineering jobs in the Rochester region. Also, In partnership with AIM Integrated Photonics, the group is conducting a study about workforce needs for the emerging integrated photonics sector.
Infrared arrays with HgCdTe as the light-sensitive layer, such as have been developed up to sizes 2048x2048 pixels for the James Webb Space Telescope, are near-ideal detectors for imaging and spectroscopy in the region ~1-5 microns. However current construction requires fabrication on CdZnTe substrates, which are expensive and limited in availability. The key to making larger (up to 14,000x14,000 pixels) and less expensive infrared detectors lies in using silicon wafer substrates, since large silicon wafers are common in the high volume semiconductor industry and their coefficient of thermal expansion is well-matched to that of the silicon readout circuits.
While the use of silicon substrates has been a major goal in the field of developing infrared detectors, the main limitation over the past 15 years has been the large lattice spacing mismatch between silicon and commonly-used infrared light-sensitive materials. The mismatch causes defects that can result in higher dark current, or valence holes that lead to reduced quantum efficiency and image persistence.
Enlisting the expertise and fabrication capabilities of Raytheon Vision Systems, detector expert Dr. D. Figer of the Rochester Institute of Technology plans to deposit the HgCdTe light-sensitive layer on silicon using the very promising technique of Molecular Beam Epitaxy (MBE). By maintaining vacuum during MBE processing, defect density has been shown to be reduced and the resulting prototype devices have achieved the anticipated performance. Very large, affordable infrared arrays is essential for making optimum use of the proposed ~30m class ground-based telescopes and their availability has clear implications for fields beyond astronomy, including medical imaging and remote sensing.
Single photon counting detectors have the potential to be the next big advancement for NASA astronomy missions. The ability to count single photons facilitates science goals that are impossible even with current state-of-the-art detectors. Single photon counting detectors are the future, and many different implementations are in development. In the next 20 years, many NASA missions requiring single photon counting will be proposed, but which single photon counting detector implementations best suit the performance needs of NASA’s astronomy programs? The goal of the proposed research is to characterize (theoretically and physically) three unique implementations of single photon counting detectors, benchmark their operation over a range of performance characteristics, and provide comprehensive justification for the superiority of one of the implementations for each of these NASA astronomy applications: exoplanet detection, high-contrast imaging, adaptive optics, and array-based LIDAR.
The research plan in this project includes simulation, characterization, and evaluation of the performance of three types of semiconductor photon counting detectors for use in NASA astronomy missions: Geiger-mode (GM) APDs, linear-mode (LM) APDs, and Electron Multiplying (EM) CCDs.
The main goal of this project is to provide the basis of comparisons for several types of fundamentally different single photon counting detectors by producing a table of comparisons and recommendations for various applications. All detectors must be sensitive to single photons, be scalable to large array formats, and have high QE (in the visible, UV, NIR, IR, and Far-IR wavelengths). This research is advancing preliminary work by adding new characterization methods and performance benchmarks, and by comparing the different devices at predetermined milestones during the project. The recommended detector(s) should function well at high readout frequencies without significant read noise (leading to improved temporal sampling), have very low noise for increased SNR at low fluence levels, and be implemented (or able to be in the near future) on large arrays. Even though single-photon counting detectors share a common performance benchmark (discerning individual quanta), differences between various implementations make some more efficient than others.
This program will have a profound impact across ground-based and space-based astronomy by dramatically reducing the cost of infrared detectors for existing facilities, as well as the next generation of extremely large telescopes. The project is continuing development of a new material system for use in astronomical infrared array detectors. The devices use HgCdTe grown on Silicon using Molecular Beam Epitaxy. In Phase I of this project, the NSF ATI program funded two cycles of design, fabrication, and testing. The devices made in this phase of the project show that the technology can meet the astronomy requirements pending further development. Testing shows that there are several challenges that prevent the devices in hand from satisfying these requirements. In this second phase, the Center for Detectors is developing a series of devices with improved design and processing. The approach is to reduce the number of material defects while maintaining high short-wavelength quantum efficiency by using proven designs. Given that these previous designs have successfully been used to address the observed non-idealities, it is believed that the new activities will be successful. The work includes: growth of new material using a thick buffer layer design, fabrication of twelve FPAs in two designs, and extensive testing between the fabrications of the two designs.
This project is advancing the knowledge of a material system that has great promise for infrared detector technology. It is also enhancing the capabilities of infrared instrumentation in astronomy by reducing cost and potentially improving performance when compared to what is available with existing technology. The technical approach has great merit because it was developed over the past 15 years and during Phase I of the project. The plan features a tight connection between design at Raytheon Vision Systems (RVS) and testing in the Center for Detectors at the Rochester Institute of Technology, continuing over 15 years of collaboration between RVS and the PI.
Metal-assisted chemical etching (MacEtch) is an anisotropic, solution-based nanofabrication process that combines the benefits of conventional wet-etching and plasma-based ion etching. The MacEtch process relies on site-specific, catalytic oxidation of a semiconductor surface by a patterned noble metal layer, followed by preferential dissolution of the selectively oxidized regions. Continuous repetition of oxidation-dissolution cycles in a single MacEtch bath results in the metal layer sinking into the semiconductor such that vertical nanostructures are left in the path of the metal layer, having geometries that are complementary to the geometry of the patterned metal. In the EINS lab, we are interested in exploring the fabrication of III-V semiconductor nanostructures using non-conventional metallic catalysts composed of carbon-nanotubes and graphene. In this manner we define novel nanofabrication paradigms that enable low-cost and clean alternatives to conventional ion-based etching procedures, offering high-aspect ratio features with atomically-abrupt sidewall termination. Novel device applications in high-efficiency solid-state lighting and tri-gated nanofin-based field effect transistors have already been demonstrated using on MacEtch fabrication.
The Center for Detectors is conducting a design study for software and data analysis for the Tomographic Ionized-carbon Mapping Experiment (TIME-Pilot) instrument, which is designed to make pioneering measurements of the redshifted 157.7 micron line of singly ionized carbon [CIIJ from the Epoch of Reionization (EoR). The EoR is the period in the Universe's history during which the first stars and galaxies formed, and whose intense ultra-violet (UV) radiation fields ionized the intergalactic medium. The New Worlds, New Horizons 2010 Astrophysics Decadal Report recognized the EoR as one of five scientific discovery areas where "new technologies, observing strategies, theories, and computations open . . . opportunities for transformational comprehension". This investigation is breaking ground for future investment from government and private funding agencies by improving our understanding of the instrument design and expected performance.
Planning activities and start up for Rochester Hub for test, assembly and packaging.
This project's long-term objective is the creation of a workforce of proficient integrated photonic circuit designers. There is a clear industry need for designers that are able to utilize Electronic Photonic Design Automation (EPDA) methodologies to effectively design functional photonic-electronic circuitry to drive the integrated photonics industry into the future. The primary goal of this project is to meet this need with the creation of integrated photonic circuit design/test content to enable educators to teach students and industrial practitioners the principles, methodologies and practical knowledge of integrated photonic circuit design.
This Major Research Instrumentation (MRI) funding is supporting the acquisition of an inductively coupled plasma reactive-ion etching (ICP-RIE) system to enable fundamental research and education in nanophotonics, nanoelectronics and nano-bio devices. The objective of this MRI acquisition is to facilitate new and existing multidisciplinary research in science and engineering, enable educational curriculum development, and promote outreach activities at Rochester Institute of Technology (RIT). The ICP-RIE system has the capability for photonic, electronic and bio device fabrication that does not exist presently at RIT and Rochester region.
The ICP-RIE system provides dry etching capability for various material systems such as compound semiconductors, dielectric materials, and metals with fast etching rate, well-controlled selectivity, and promising uniformity. The instrument is essential to enable fundamental research and education on III-Nitride based light emitting diodes (LEDs) and lasers, seamless integration of robust and low-powered III-V quantum dot (QD) lasers with silicon photonics, III-V tunneling field effect transistor, memory devices for computing, QD and nanowire photovoltaics, III-Nitride photodetectors for inertial confinement fusion research, nanoplasmonic devices, and nan-bio devices for efficient biomolecule transfer. The instrument will be the first ICP dry etcher tool at RIT, which will be shared by research groups across all disciplines in science and engineering with students trained from Microsystems Engineering Ph.D. program and Ph.D. in Engineering program. The tool will also be shared by external research groups in Rochester region to enhance research and collaborations between RIT and other colleges, national labs, and small businesses in the region.
The ICP-RIE system will be designated as a shared user facility, available to new curriculum and lab section development on device fabrications for both undergraduate and graduate students at RIT, whom can be trained for next-generation scientists and engineers. The fabrication capability provided by the proposed instrument benefits curriculum development at RIT for several fundamental courses and lab sections focused on nanofabrication and semiconductor devices. Demonstration experiments on photonic and electronic devices can also be designed to K-12 students and teachers through RIT outreach activities by the use of the dry etcher, which can stimulate K-12 students' interest to pursue science, technology, engineering, and mathematics (STEM) disciplines in the future. Connectivity with such demonstration experiments will also be promoted to train existing women and underrepresented minority students at RIT.
This program is developing flexible, low-cost packaging techniques for largescale, integrated optoelectronic systems based on heterogeneously integrated photonic and electronic chips.
The objective of this research is to explore ultracompact graphene optical modulators for future on-chip optical communications. The approach is to systematically explore the unique electro-optic properties of graphene, and to greatly enhance the interaction of graphene with light based on novel waveguides and platforms. In particular, graphene in a waveguide can be tuned with anomalous optical properties with a suitable gate voltage, which is being employed to develop the modulators.
This project is systematically exploring novel graphene-sandwiched optical waveguides based on the unique properties of graphene. This research is one of the first experimental attempts to demonstrate optical modulators at nanoscale, and one of the first systematic explorations of graphene for all-optic modulation. The research results may revolutionize nanophotonic technology and on-chip optical interconnects, and contribute to the fundamental theory and techniques for newly developed Graphene Optoelectronics and Graphene and 2D Semiconductor Physics.
Graphene is a topic that is of great interest to the general public. The outreach activity, "From Graphite to Graphene", is helping STEM education by introducing K-12 students to the science and fabrication of nanotechnology for a wide range of applications. The students involved in this research are participating in nanotechnology development, and the results developed from the research activities will be incorporated into several college courses. Collaboration with external companies may commercialize valuable products for industrial and military applications. Under-represented students from Women in Engineering and North Star Program are involved in this project.
Stellar images taken with telescopes and detectors in space are usually undersampled, and to correct for this, an accurate pixel response function is required. The standard approach for HST and KEPLER has been to measure the telescope PSF combined ("convolved") with the actual pixel response function, super-sampled by taking into account dithered or offset observed images of many stars. This combined response function has been called the "PRF". However, using such results has not allowed astrometry from KEPLER to reach its full potential. Given the precision of KEPLER photometry, it should be feasible to use a pre-determined detector pixel response function (PRF) and an optical point spread function (PSF) as separable quantities to more accurately correct photometry and astrometry for undersampling. Wavelength (i.e. stellar color) and instrumental temperature should be affecting each of these differently.
Discussion of the PRF in the "KEPLER Instrument Handbook" is limited to an ad-hoc extension of earlier measurements on a quite different CCD. It is known that the KEPLER PSF typically has a sharp spike in the middle, and the main bulk of the PSF is still small enough to be undersampled, so that any substructure in the pixel may interact significantly with the optical PSF.
Both the PSF and PRF are probably asymmetric. The Center for Detectors is measuring the PRF for an example of the CCD sensors used on KEPLER at sufficient sampling resolution to allow significant improvement of KEPLER photometry and astrometry, in particular allowing PSF fitting techniques to be used on the data archive.
Charge coupled detectors (CCDs) are inoperable below 120K due to electron freeze-out effects and therefore, problematic in cryogenic applications. An alternative optical sensing technology, the scientific complementary metal-oxide-semiconductor (sCMOS) detector, offers the possibility of mega-pixel science-grade optical cameras operable to - IOK. The promise of a fully cryogenic optical detector is a compelling technology for NASA because it does not require active heating in the space environment. Such a detector enables instruments ranging from actively-cooled star trackers for sounding rockets to low-temperature deep space cameras. As a first step, The Center for Detectors is developing and flying an attitude-sensing camera employing a low noise, high quantum efficiency cryogenic sCMOS detector on a Black Brant IX sub-orbital vehicle. Images from the T=77K 5.5 mega-pixel sensor is processed by on-board software and pointing information is used to dynamically control the attitude of the payload with gyroscopes. The instrument design, fabrication, flight operations and data analysis is being performed by a diverse, multi-disciplinary team of undergraduate students to provide hands-on experience on a flight project under the leadership of a graduate student mentor and an experienced PI. The students are responsible for mechanical, optical, and electronic engineering activities; firmware and algorithm development; flight planning and operations; and project management, documentation control, and reporting. Following a successful initial flight, this system will fly on a NASA astrophysics payload to measure extragalactic light from the cosmic infrared background.
The Center for Detectors is developing solutions to key challenges in achieving high-efficiency single-mode GaN-based ultraviolet (UV) lasers with wavelength ranging from 220 nm up to 300 nm. Particularly, the research focuses on the fundamental physics understanding of the valence band structure of lll-Nitride wide bandgap gain active region, and develop promising solutions on nanostructured quantum wells and fabrication approach of large area GaN-based UV laser arrays. These lasers are a promising candidate for various naval applications in sensing and communication.
The objective of this project is to support AIM Academy (the education arm of AIM Photonics) by providing education modules for integrated photonics design, manufacturing, packaging and testing. We are also working to educate students, workforce, veterans and the community with: short courses, degree courses, establish an integrated photonics practice facility, assess workforce needs and develop an ME degree in Integrated Photonics Manufacturing in collaboration with MIT.
The Center for Detectors received funds for a measurement system to enable Quantum Silicon Photonics research. The system consists of a low-noise tunable laser and single photon detectors.
The Rochester Institute of Technology team is responsible for the delivery of a cryogenically-operable star tracking camera for attitude control of the CIBER-2 payload. RIT is building, testing, and delivering this camera to Caltech for integration into the full experiment by the beginning of Year 2. RIT is also responsible for delivering the associated documentation and interface information to both Caltech and NASA by the end of Year 2. The RIT team is also responsible for assisting with: (1) overall instrument design; (2) integration of the payload system; (3) laboratory testing and characterization; (4) flight planning and logistical requirements; (5) deployment and flight efforts; (6) data reduction and calibration; and (7) science extraction.