Research Topics

Atomic and molecular systems provide a set of highly precise and accessible energy level transitions that can be used as stable frequency references for precision timing. Some questions we are seeking insight into are:

• How can we reduce the size of chip-scale atomic clocks? 
• Can we design clocks with atomic references at much higher frequencies that are used today (e.g., from gigahertz to terahertz) to improve timing accuracy and stability? Can we miniaturize these clocks so they can be ubiquitously adopted in fielded applications?
• How can we rapidly and accurately synchronize multiple independent clocks that are spatially separated?
• Beyond the commonly used systems, what other atomic or molecular gases have the potential to achieve very high timing precision?  Can the ancillary support structures also be miniaturized and packaged?

Though there are many navigation techniques that can and do complement GPS in current operations, even the best of these techniques have limitations.  Terrain registration, as a simple example, only works over feature-rich land, not over open water.  Other approaches, such as signals of opportunity, rely on the presence of RF signals.  Thus far, no “silver bullet” complementary PNT approaches exist.  Instead, navigation systems synthesize multiple navigation techniques together to generate a coherent navigation update. For example, the navigation system may combine inputs from sensors already on the platform – inertial, radar and imaging systems– and new sensors installed solely for complementary PNT. Open research questions include:

• How to optimally combine information from various APNT sources?
• How can information added from various sensors be quantified?
• Computationally efficient and modular algorithms for combining information from APNT sources

The ability to measure celestial objects across different spectral regions, using advanced imaging processing techniques, utilizing ultrasensitive detection techniques, and/or leveraging adaptive optics can enable significant increases in observational capacity and ultimately better positional accuracies. We seek to foster a number of different modalities that can improve the imaging of celestial objects (including those in Earth orbit). Some questions that we are interested in are:

• How can non-centrosymmetric optics be used to improve compact telescope designs (particularly by removing obscurants)?
• Can size-, weight-, and power-constrained focal plane arrays be built that examine multiple spectral regions? Can multiple focal plane arrays be used in highly limited form factors to increase spectral ranges?
• Are there novel methods for sensing and correcting incoming light through highly degrading environments or rapidly changing conditions?
• How can field of view be maximized while limiting or eliminating aberrations (spherical, chromatic, etc.)? Are there techniques, methods, or processes for achieving very high fields of view?
• Advanced, lightweight telescope concepts and designs
• Very high bandwidth camera and image processing throughput for examining wide fields of view and/or multiple, independent fields of view.

Magnetic anomaly navigation (MagNav) is an unjammable and environment-agnostic navigation modality that utilizes earth’s magnetic anomaly field to estimate position. Such anomaly fields arise from globally distributed crustal deposits of magnetic material. Separate from earth’s core field, these deposits generate magnetic signatures high in spatial frequency and stable in time. This anomaly field must be extracted from scalar magnetometer measurements, which capture the earth’s core field and platform magnetic noise in addition to the desired signal. Once isolated, the anomaly signal is compared to a geo-referenced anomaly map to estimate position. Open MagNav research questions include:

• Current MagNav systems are size-, weight-, and power-intensive. How can system size be reduced while maintaining performance?
• How can MagNav be rapidly integrated on new vehicles while minimizing the negative effects of platform magnetic noise?
• What are the optimal filter architectures for accumulating and integrating magnetic anomaly signals into a navigation system?

We seek advancements in atomic and molecular sensing of electric and magnetic field, such as:

• Use of Rydberg atoms to simultaneously sense both electric (RF) and magnetic fields. Can detectability be increased?  Can the detection be shown to be vectorized?
• Atomic gravimetry for precision sensing of gravity in highly constrained (size, weight, and power) packages and/or unstable platforms (e.g., moving vehicles, airplanes, ships, etc.).
• Use of atomic or molecular gases for very high precision magnetic field detection (magnitude or vectorized).
• Low-dimensional materials for sensing acoustics (air or underwater) at very specific frequencies (narrowband) and very high detectabilities.
• Ionic, atomic, dopant, or vacancies in materials that can be used for magnetic field sensing, such as nitrogen vacancies in diamond, dopants or inclusions in optical fiber for Faraday rotation detection, or magnetic dopants in quantum dots.

A new generation of materials has shown that when the material size becomes similar to or less than the size of relevant quantum wavefunctions, new capabilities and novel physics can be achieved.  We seek a greater understanding of how phenomena in these materials (largely at room temperature) can be used in chip-scale devices and packaging for very sensitive detection or manipulation of electric, magnetic, acoustic, optical, or quantum behaviors.  Topics may include:

• Spontaneous self-assembly of materials to form a simple device or sensor.
• High-performance materials (e.g., graphene, topological insulators, phase-change materials, etc.) that can be used for sensors that manipulate light.
• Electrical control of light-matter interactions, such as rapid control over indices of refraction, high-speed manipulation of reflection/absorption/transmission, or coherent energy transfer to/from incoming light in a narrowband frequency region.
• Materials that can be used for novel acoustic sensors.
• Materials for packaging and sensing in harsh environments.

The use of precision-controlled light using unique geometries and tailored refractive indices enables a radical reduction in the size, weight, and power across the APNT spectrum.  We seek to explore topics in photonics such as:

• Squeezed light for improvements in accelerometry, imaging, or sensing.
• Ultrasensitive and size-reduced sensing of rotations and linear movements in photonics.
• The use of topological photonics for novel APNT solutions.
• Flat optics for precision imaging and/or optical control.
• Photonics for observing through degraded optical environments or unique spectral regions.
• Photonics for detecting, sensing, or measuring vibrations and acoustic perturbations.
• Broadband, high-efficiency, and alignment tolerant PIC waveguide coupling mechanisms.