NASA Tech Briefs, March 1992

Topics include: New Product Ideas; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

Design and development for the Rearsection of the KATRIN experiment

Die Rearsection stellt verschiedene Werkzeuge zur Kalibration und Überwachung des Quellbereichs des KATRIN Experiments zur Verfügung. Diese Arbeit stellt die wichtigsten Design- und Entwicklungsschritte an der Rearsection dar. Dazu gehören beispielsweise die Optimierung des elektromagnetischen Designs der integrierten Elektronenkanone wie auch verschiedene Testexperimente zur Finalisierung der "Rear Wall" des KATRIN Experiments

Towards many-body physics with Rydberg-dressed cavity polaritons

An exciting frontier in quantum information science is the creation and manipulation of bottom-up quantum systems that are built and controlled one by one. For the past 30 years, we have witnessed signi cant progresses in harnessing strong atom- eld interactions for critical applications in quantum computation, communication, simulation, and metrology. By extension, we can envisage a quantum network consisting of material nodes coupled together with in nite-dimensional bosonic quantum channels. In this context, there has been active research worldwide to achieve quantum optical circuits, for which single atoms are wired by freely-propagating single photons through the circuit elements. For all these systems, the system-size expansion with atoms and photons results in a fundamental pathologic scaling that linearizes the very atom- eld interaction, and signi cantly limits the degree of non-classicality and entanglement in analog atom- eld quantum systems for atom number N 1. The long-term motivation of this MSc thesis is (i) to discover new physical mechanisms that extend the inherent scaling behavior of atom- eld interactions and (ii) to develop quantum optics toolkits that design dynamical gauge structures for the realization of lattice-gauge-theoretic quantum network and the synthesis of novel quantum optically gauged materials. The basic premise is to achieve the strong coupling regime for a quantum many-body material system interacting with the quantized elds of an optical cavity. Our laboratory e ort can be described as the march towards \many-body QED," where optical elds acquire some properties of the material interactions that constrain their dynamical processes, as with quantum eld theories. While such an e ort currently do not exist elsewhere, we are convicted that our work will become an essential endeavor to enable cavity quantum electrodynamics (QED) in the bona- de regime of quantum many-body physics in this entanglement frontier. In this context, I describe an example in Chapter 2 that utilizes strong RydbergRydberg interactions to design dynamical gauge structures for the quantum square ice models. Quantum uctuations driven by cavity-mediated in nite-range interaction stabilize the quantum-gauged system into a long-range entangled quantum spin liquid that may be detected through the time-ordered photoelectric statistics for photons leaking out of the cavity. Fractionalized \spinon" and \vison" excitations can be manipulated for topological quantum computation, and the emergent photons of arti cial QED in our lattice gauge theoretic system can be directly measured and studied. The laboratory challenge towards strongly coupled cavity Rydberg polaritons encompasses three daunting research milestones that push the technological boundaries beyond of the state-of-the-arts. In Chapter 3, I discuss our extreme-high-vacuum chamber (XHV) cluster system that allows the world's lowest operating vacuum environment P ' 10 Torr for an ultracold AMO experiment with long background-limited trap lifetimes. In Chapter 4, I discuss our ultrastable laser systems stabilized to the ultra-low-expansion optical cavities. Coupled with a scalable eld-programmable-gate-array (FPGA) digitalanalog control system, we can manipulate arbitrarily the phase-amplitude relationship of several dozens of laser elds across 300 nm to 1550 nm at mHz precision. In Chapter 5, we discuss the quantum trajectory simulations for manipulating the external degrees of freedom of ultracold atoms with external laser elds. Electrically tunable liquid crystal lens creates a dynamically tunable optical trap to move the ultracold atomic gases over long distance within the ultra-high-vacuum (UHV) chamber system. In Chapter 6, I discuss our collaborative development of two science cavity platforms { the \Rydberg" quantum dot and the many-body QED platforms. An important development was the research into new high-index IBS materials, where we have utilized our low-loss optical mirrors for extending the world's highest cavity nesse F 500k! We discuss the unique challenges of implementing optical cavity QED for Rydberg atoms, which required tremendous degrees of electromagnetic shielding and eld control. Single-crystal Sapphire structure, along with Angstrom-level diamond-turned Ti blade electrodes, is utilized for the eld compensation and extinction by > 60 dB. Single-crystal PZTs on silica V-grooves are utilized for the stabilization of the optical cavity with length uncertainty less than 1=100 of a single nucleon, along with extreme level of vibration isolation in a XHV environment. The capability to perform in-situ RF plasma cleaning allows the regeneration of optical mirrors when coated with a few Cs atoms. Lastly but not the least, we combine single-atom resolution quantum gas microscopy technique with superpixel holographic algorithm to project arbitrary real-time recon gurable di raction-limited optical potential landscapes for the preparation of low-entropy atom arrays

NASA Tech Briefs, February 1993

Topics include: Communication Technology; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

NASA Tech Briefs, May 1996

Topics include: Video and Imaging;Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery/Automation; Manufacturing/Fabrication; Mathematics and Information Sciences; Life Sciences; Books and Report

Electromagnetic Measurements with the KATRIN Pre-Spectrometer

The KArlsruhe TRItium Neutrino (KATRIN) Experiment will investigate the `electron antineutrino` mass with a sensitivity of 200meV/c2. A key to reach this sensititvity is a significant improvement of the MAC-E filter (Magnetic Adiabatic Collimation with Electrostatic filter) technology for the energy analysis of beta decay electrons. This thesis details the commissioning of the KATRIN pre-spectrometer, featuring a novel MAC-E filter design with regard to vacuum and electrostatic filtering

Technology 2001: The Second National Technology Transfer Conference and Exposition, volume 2

Proceedings of the workshop are presented. The mission of the conference was to transfer advanced technologies developed by the Federal government, its contractors, and other high-tech organizations to U.S. industries for their use in developing new or improved products and processes. Volume two presents papers on the following topics: materials science, robotics, test and measurement, advanced manufacturing, artificial intelligence, biotechnology, electronics, and software engineering

Cooling the Center-of-Mass Motion of a Diamond Nanocrystal in a Magneto-Gravitational Trap

A magneto-gravitational trap for micro/nanometer sized diamagnetic particles, such as diamond nanocrystals, is tested and characterized. After exploring various other systems, such as a suspended graphene beam and an optical trap, this magneto-gravitational nanomechanical trapping system for diamond with nitrogen-vacancy (NV) centers presents unique advantages for experiments in fundamental quantum mechanics. Those include, for example, the generation of large quantum superposition states and tests of quantum gravity. Features are demonstrated for this system, such as stable and passive levitation from atmospheric pressure to high vacuum, low resonant frequencies and damping rates, and cooling of the center-of-mass motions to below 1 K. The construction of the trap, vacuum system, optics, and motion detection electronics are described in detail

Approaching Quantum-limited Electrometry in the Single-photon Regime

Mesoscopic quantum systems currently serve as essential building blocks in many quantum information and metrology devices. This thesis investigates the potential of quantum-limited detection in a mesoscopic electrometer named the cavity-embedded Cooper pair transistor (cCPT). As one application, this charge detector can act as the basis for an optomechanical system in the single-photon strong coupling regime. The realization of this scheme would entail near quantum-limited, ultra-sensitive electrometry at the single-photon level, the feasibility of which is studied at length in this thesis. On the one hand, we approach this question using a fundamental, first-principles study, where an operator scattering model is used to analyze the quantum dynamics of this device. While the cCPT is inherently a tunable, strongly nonlinear system affording diverse functionalities, we restrict our analysis to a necessary first investigation of its linear charge sensing capabilities, limiting to low pump powers corresponding to an average cavity photon number \u3c1. Assuming realizable cCPT parameters, we predict the fundamental, photon shot noise-limited charge sensitivity to be 0.12 μe/√Hz, when the pumped cavity has an average of one photon. In practice, this lower bound is difficult to achieve using conventional detection approaches, owing mainly to the low-frequency noise caused by the coupling of two-level systems to the cCPT. Hence we further employ a top-down approach where the gate-dependent tunability of the cCPT is used to implement a feedback scheme derived from the Pound-Drever-Hall locking technique. This scheme effectively reduces the fluctuations due to intrinsic charge noise. In particular, we report a reduction in the resonant frequency fluctuations caused by the internal charge noise over a bandwidth of ~1.4 kHz when the cavity is driven at an average photon number n=10, and a bandwidth of 11 Hz for average n=1. Our technique can be generalized to achieve frequency stabilization in tunable microwave resonators that play a vital role in today\u27s quantum computing architectures, thereby moderating the limitations in detection caused by the intrinsic 1/f-noise on such circuit devices. As a concluding study, we incorporate these feedback techniques to improve the charge sensitivity of the cCPT, thus demonstrating the potential of near quantum-limited charge detection using this device