1985 — 1991 |
Elliott, Daniel |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Pyia: Nonlinear Interaction of Laser Radiation With Atomic System @ Purdue Research Foundation |
0.907 |
1991 — 1994 |
Elliott, Daniel |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Interfering Optical Interactions (Physics) @ Purdue Research Foundation
Recently, experiments have been performed which demonstrate that interference between alternative excitation pathways in the laser excitation of atoms and molecules can be observed and controlled using non-linear conversion techniques. In order to obtain a better understanding of these phenomena, it is proposed to extend the work on measuring phase differences to (a) the effect of interfering processes on photo-electron angular distributions, (b) phase differences between the fundamental and third harmonic in third harmonic generations, (c) two-photon resonant cases and (d) control of relative production rates of excited states in atomic barium.
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0.907 |
2008 — 2011 |
Elliott, Daniel Chen, Yong |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Quantum Control of Polar Molecules For Quantum Information and Quantum Computing
Quantum Control of Polar Molecules for Quantum Information and Quantum Computing
Abstract:
Quantum computers promise to revolutionize our ability to perform computation and solve complicated problems. However, quantum computers are difficult to build. It remains unclear what quantum systems will eventually be used for implementation of a ?scalable? quantum computer, which needs to operate on a large number of quantum bits (qubits) in order to outperform classical computers. This research develops a novel technology using quantum coherent control to produce and manipulate a large number of cold polar molecules. Such polar molecules have many appealing features to be used as qubits. The investigators use all-optical methods to achieve parallel yet local and individual control of many polar molecules. This work can lead to new approaches toward scalable quantum computing. Graduate and undergraduate students will participate in this research in an interdisciplinary team and learn at the forefront of optics and photonics, atomic and molecular physics, and quantum information science.
This research develops a novel technology using quantum coherent control in the production and manipulation of cold polar molecules, motivated by potential applications of such polar molecules in quantum information processing and computing. The investigators combine two powerful techniques in modern molecular physics, photoassociation and phase coherent control, to explore novel methods of quantum control of polar molecules, using an optically-based approach to achieve local yet massively-parallel individual control of both the density and orientation of polar molecules. This work could lead to the development of new protocols and schemes of scalable quantum information processing and computing.
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0.961 |
2010 — 2014 |
Elliott, Daniel |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Measurements of the Parity Non-Conservation Amplitude in Atomic Cesium For Improved Tests of the Standard Model and Beyond
This research will provide a long-sought independent check of the Parity Non-Conserving (PNC) measurement in cesium, and especially of the nuclear spin dependence of these measurements. Tests of the Standard Model, the theoretical description of the physical world that unifies two of the four fundamental forces (the weak forces and electromagnetic forces), are critical to our understanding of matter at the atomic and nuclear level. New laboratory measurements of higher precision will allow for an even more precise determination of the weak charge, a fundamental quantity within the Standard Model. Even more important will be measurements of the PNC interaction on the different hyperfine transitions, which will probe higher-order effects such as the nuclear anapole moment. Prior measurements of nucleon-nucleon scattering in atomic systems have produced constraints of coupling constants that are at odds with those from high-energy scattering measurements, and the proposed measurements are designed to help resolve these discrepancies.
This work will (1) advance our understanding of interactions beyond those typically encountered in atomic physics, (2) lead to advances in detection of weak interactions, and (3) provide educational opportunities for graduate and undergraduate students in disciplines of Physics and Engineering. In addition to mastery of topics of current interest, students in the laboratory learn important technical skills such as optics and lasers, electronics, data analysis, and computer programming. The PI is committed to education at the graduate and undergraduate level, promoting diversity in science and engineering, and integrating research and education. Participation by undergraduate students in the PI's laboratory is an active facet of this program.
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0.961 |
2011 — 2013 |
Elliott, Daniel Weiner, Andrew [⬀] Chen, Yong Chakrabarti, Raj (co-PI) [⬀] |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Mri: Acquisition of Self-Referenced Frequency Comb For Atomic-Molecular-Optical Physics and Optical Signal Processing Research
Research Objectives and Approach
The objective of this research is to investigate applications of optical frequency combs in photonic signal processing and atomic-molecular-optical (AMO) physics. The approach is to acquire a state of the art, commercial frequency comb laser to enable new experimental studies.
Intellectual Merit
In ultrafast photonics the frequency comb will enable generation of optical and radio-frequency signals with instantaneous bandwidth and long-term jitter properties significantly better than available by conventional technologies. In AMO physics research, the frequency comb will enable driving coherent optical transitions involving very different transition frequencies, and will be an invaluable tool, for example, to create ground state molecules via photoassociation for current research aiming to use such molecules for quantum computing. Furthermore, the proposed equipment is expected to catalyze new interdisciplinary collaborations involving both disciplines.
Broader Impacts
The proposed equipment will provide rich opportunities for broad student training in areas of cutting-edge technology and enable new research impacting optical and wireless communications, both areas with direct societal impact, and quantum computing, an emerging area with potential for revolutionary impact in the long term. Broader impact is also anticipated through a variety of activities in which the proposing faculty are engaged. For example, Weiner is currently Chair of the National Academy of Engineering?s Frontiers of Engineering conference, considered to be an important career development opportunity for future engineering leaders, while Elliott is active in diversity issues, as evidenced by his term as Director of Graduate Recruitment and Retention Programs at Purdue?s College of Engineering.
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0.961 |
2016 — 2019 |
Elliott, Daniel |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Towards Precision Measurements of Atomic Parity Violation Using Two-Pathway Coherent Control
The four fundamental forces of the physical universe are gravitational, electromagnetic, weak (responsible for radioactive decay of particles), and strong (the binding force that holds the nuclei of atoms together). A great deal about these forces has been learned over the years, and a theoretical model that unifies and summarizes our understanding of three of these forces (electromagnetic, weak, and strong), known as the Standard Model, has been extremely precise in many of its predictions. There still persist, however, several very important open questions that cannot be explained within the Standard Model, or which fall outside the energy range in which the Standard Model is expected to be valid (such as conditions that existed during the very early stages of the universe). One of these is the existence and properties of dark matter: matter within our universe that we know exists (because of the slowing expansion of the universe), but which does not interact with regular matter in the universe through any means that we have been able to detect. Another is the possible existence of particles that are so massive that they have not yet been generated or observed at the large high-energy particle accelerators (such as the Large Hadron Collider in Switzerland). Yet a third area in which to search for physics beyond the Standard Model is to look for the indirect influence of the proposed extensions on extremely precise measurements of weak optical transitions in atoms. This is the focus of this research effort, which can help guide the answers to these fundamental questions about the universe.
The principal investigator and his team will carry out new, higher-precision measurements of weak-force-induced transition amplitudes in atomic cesium. This atom was the focus of prior measurements by the group of Carl Wieman in Boulder in the 1990's, and these measurements of the parity violating amplitude are still the most precise reported for any element. There exists, however, a need to carry out atomic parity violation measurements at an even higher precision. Such a measurement will allow a more precise determination of the weak charge of the nucleus, and from that, an improved determination of the electroweak mixing angle at low momentum transfer. The energy dependence (or "running", as it is called) of this mixing angle, as measured through scattering measurements at various energies, places important constraints on conjectured massive bosons in theories that extend the standard model. These measurements also guide searches for dark matter candidates. Atomic parity violation measurements can also be used to determine the anapole moment of the atomic nucleus. This moment, resulting from weak interactions within the nucleus, provides the leading contribution to the nuclear spin dependence of the parity violating amplitude. To date, the Boulder group's measurement of the anapole moment of cesium is the only successful measurement in any element. Since this result is about twice as large as expected, and its magnitude is still not understood, there is a need for a new measurement to either verify or refute its magnitude. The goal of the present project is to return to cesium for a set of new, high-precision measurements that will address these goals. The principal investigator will apply a two-pathway coherent control technique to these measurements. One set of measurements are centered on the 6s - 7s transition, visited previously by Wieman, while a second set will examine similar effects in the ground state transition between hyperfine components.
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0.961 |
2019 — 2024 |
Elliott, Daniel |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Precision Measurement of Parity Non-Conserving, Weak-Force Induced Transitions in Atomic Cesium
We understand the universe in which we live through four fundamental forces: gravitational, electromagnetic, weak (responsible for radioactivity and beta decay), and strong (which provides the force that binds atomic nuclei together). A theoretical framework that unifies three of these forces (electromagnetic, weak and strong) is known as the standard model, and has been very successful at explaining a broad range of observables and predicting others. There are, however, several notable effects that the standard model has not been able to explain, including the preponderance of regular matter in the universe (but very little anti-matter), and the existence and nature of dark matter and dark energy. The evidence of the existence of dark matter is provided by observations of the rotation of galaxies. From this, we know that the universe contains much more matter than we have been able to observe. But we know very little about what this "dark" matter is, or how, other than through gravity, it interacts with the matter that we can observe. In this project, the principal investigator and his team will use precision measurements of extremely weak optical interactions of a laser field with cesium atoms to test the standard model, and to search for signatures of physical effects that lie outside the realm of the standard model.
The Principal Investigator and his research team are developing two measurement techniques to probe the weak force interactions in atomic cesium. Each measurement technique is a variant of two-color coherent control, in which the amplitudes for two transitions in the optical or radio-frequency range interfere with one another. One measurement, based on the 6s 2S1/2 → 7s 2S1/2 transition, is designed to provide an improved value of the weak charge of the cesium nucleus. The second, based on the 9.19 GHz transition between the hyperfine components of the ground state, is due solely to nuclear-spin dependent contributions such as the anapole moment of the nucleus. Atomic cesium was, of course, the choice of Wieman for his 1997 work, and that group's measurement is still the most precise measurement of the weak charge in any atomic species. Cesium is also the only species in which the nuclear anapole moment has been observed. The degree to which the measurement of the weak charge agrees with the standard model prediction will place constraints upon various models of physics beyond the standard model. The coherent control technique is expected to result in a reduction of the susceptibility of the measurement to systematic errors, critical for the success of these measurements.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
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0.961 |