1,938 research outputs found

    Laser Technologies for Applications in Quantum Information Science

    Get PDF
    Scientific progress in experimental physics is inevitably dependent on continuing advances in the underlying technologies. Laser technologies enable controlled coherent and dissipative atom-light interactions and micro-optical technologies allow for the implementation of versatile optical systems not accessible with standard optics. This thesis reports on important advances in both technologies with targeted applications ranging from Rydberg-state mediated quantum simulation and computation with individual atoms in arrays of optical tweezers to high-resolution spectroscopy of highly-charged ions. A wide range of advances in laser technologies are reported: The long-term stability and maintainability of external-cavity diode laser systems is improved significantly by introducing a mechanically adjustable lens mount. Tapered-amplifier modules based on a similar lens mount are developed. The diode laser systems are complemented by digital controllers for laser frequency and intensity stabilisation. The controllers offer a bandwidth of up to 1.25 MHz and a noise performance set by the commercial STEMlab platform. In addition, shot-noise limited photodetectors optimised for intensity stabilisation and Pound-Drever-Hall frequency stabilisation as well as a fiber based detector for beat notes in the MHz-regime are developed. The capabilities of the presented techniques are demonstrated by analysing the performance of a laser system used for laser cooling of Rb85 at a wavelength of 780 nm. A reference laser system is stabilised to a spectroscopic reference provided by modulation transfer spectroscopy. This spectroscopy scheme is analysed finding optimal operation at high modulation indices. A suitable signal is generated with a compact and cost-efficient module. A scheme for laser offset-frequency stabilisation based on an optical phase-locked loop is realised. All frequency locks derived from the reference laser system offer a Lorentzian linewidth of 60 kHz (FWHM) in combination with a long-term stability of 130 kHz peak-to-peak within 10 days. Intensity stabilisation based on acousto-optic modulators in combination with the digital controller allows for real-time intensity control on microsecond time scales complemented by a sample and hold feature with a response time of 150 ns. High demands on the spectral properties of the laser systems are put forward for the coherent excitation of quantum states. In this thesis, the performance of active frequency stabilisation is enhanced by introducing a novel current modulation technique for diode lasers. A flat response from DC to 100 MHz and a phase lag below 90° up to 25 MHz are achieved extending the bandwidth available for laserfrequency stabilisation. Applying this technique in combination with a fast proportional-derivative controller, two laser fields with a relative phase noise of 42 mrad for driving rubidium ground state transitions are realised. A laser system for coherent Rydberg excitation via a two-photon scheme provides light at 780 nm and at 480 nm via frequency-doubling from 960 nm. An output power of 0.6 W at 480 nm from a single-mode optical fiber is obtained . The frequencies of both laser systems are stabilised to a high-finesse reference cavity resulting in a linewidth of 1.02 kHz (FWHM) at 960 nm. Numerical simulations quantify the effect of the finite linewidth on the coherence of Rydberg Rabi-oscillations. A laser system similar to the 480 nm Rydberg system is developed for spectroscopy on highly charged bismuth. Advanced optical technologies are also at the heart of the micro-optical generation of tweezer arrays that offer unprecedented scalability of the system size. By using an optimised lens system in combination with an automatic evaluation routine, a tweezer array with several thousand sites and trap waists below 1 μm is demonstrated. A similar performance is achieved with a microlens array produced in an additive manufacturing process. The microlens design is optimised for the manufacturing process. Furthermore, scattering rates in dipole traps due to suppressed resonant light are analysed proving the feasibility of dipole trap generation using tapered amplifier systems

    Development and testing of an FPGA-controlled switched-integrator current amplifier for use in scanning tunnelling microscopy

    Get PDF
    The scanning tunnelling microscope (STM) is a very powerful analytic tool capable of achieving atomic resolution. Unfortunately, the STM is restricted to samples that are sufficiently conductive to allow adequate tunneling current for feedback control. The amplifier used to measure the tunneling current is the critical limiting component. If the amplifier could be made more sensitive, the STM could be operated at lower tunneling currents allowing lower conductivity samples to be studied. Most amplifiers used in STM employ a resistor feedback design, which become unstable at high gain necessitating a tradeoff between gain and bandwidth. One way to circumvent that stability problem is to use a capacitor feedback design (switched integrator), which does not exhibit the same stability problem. This comes at the expense of added complexity because the output is the integral of the current and needs to be periodically reset. In this project, a switched-integrator current amplifier is constructed and explored. It consisted of an analog switched integrator controlled by a field-programmable-gate-array (FPGA) with a 16-bit analog-to-digital converter and an 18-bit digital-to-analog converter. A viable prototype was created which allowed for the exploration of the gain, phase, and time delay of such systems. This exploration helped further characterize the important design considerations and trade-offs necessary for such a system. A design sequence is proposed that allows for optimal planning based on the desired tunneling current and system bandwidth

    Exploring Perovskite Photodiodes:Device Physics and Applications

    Get PDF

    Developing a Microwave Quantum Memory with Rare-Earth Doped Crystals

    Get PDF
    Rare-earth doped crystals have attracted a significant amount of attention for use in quantum systems. Available, long-lived, optical and microwave transitions has lead to proposals for quantum transduction and quantum memories, both of which are important in building large scale quantum networks. Ensembles of rare-earth spins can be coupled to superconducting resonators, and high coupling strengths (with cooperativity > 1) readily achievable. While such systems have been constructed, a useful quantum memory which exploits highly coherent transitions has not yet been developed in the microwave domain. In this thesis we couple high-Q superconducting resonators to Yb doped YSO. The spin system of Yb:YSO is explored and the main causes of decoherence are outlined, these are found to be instantaneous diffusion and spectral diffusion. In the process of this, new techniques are developed to determine decoherence sources, where nuclear spins within the YSO crystal are found to limit coherence. Two different regimes are explored to increase the coherence time. Using optimal field orientations and high magnetic field magnitudes, the coherence time is extended to (6±2) ms. While the zero field clock transition is used, along with isotopic purification, to reach the same time ((6±1) ms). Using these techniques to increase coherence, the foundations for a microwave quantum memory with Yb:YSO are laid. Cooperativities > 1 are measured for three different Yb spin systems, this allows for these spin systems to be used in memory protocols and reach unit efficiency. New pulse sequences using adiabatic fast passage are developed to provide control over the spin ensemble and for memory protocols. Finally, we use the knowledge from all of these studies to propose a system which would form the basis of an efficient, long-lived microwave quantum memory using FIB-milled Yb:YSO

    Beam scanning by liquid-crystal biasing in a modified SIW structure

    Get PDF
    A fixed-frequency beam-scanning 1D antenna based on Liquid Crystals (LCs) is designed for application in 2D scanning with lateral alignment. The 2D array environment imposes full decoupling of adjacent 1D antennas, which often conflicts with the LC requirement of DC biasing: the proposed design accommodates both. The LC medium is placed inside a Substrate Integrated Waveguide (SIW) modified to work as a Groove Gap Waveguide, with radiating slots etched on the upper broad wall, that radiates as a Leaky-Wave Antenna (LWA). This allows effective application of the DC bias voltage needed for tuning the LCs. At the same time, the RF field remains laterally confined, enabling the possibility to lay several antennas in parallel and achieve 2D beam scanning. The design is validated by simulation employing the actual properties of a commercial LC medium

    A Sub-Electron-Noise Multi-Channel Cryogenic Skipper-CCD Readout ASIC

    Full text link
    The \emph{MIDNA} application specific integrated circuit (ASIC) is a skipper-CCD readout chip fabricated in a 65 nm LP-CMOS process that is capable of working at cryogenic temperatures. The chip integrates four front-end channels that process the skipper-CCD signal and performs differential averaging using a dual slope integration (DSI) circuit. Each readout channel contains a pre-amplifier, a DC restorer, and a dual-slope integrator with chopping capability. The integrator chopping is a key system design element in order to mitigate the effect of low-frequency noise produced by the integrator itself, and it is not often required with standard CCDs. Each channel consumes 4.5 mW of power, occupies 0.156 mm2{^2} area and has an input referred noise of 2.7μνrms{\mu\nu}_{rms}. It is demonstrated experimentally to achieve sub-electron noise when coupled with a skipper-CCD by means of averaging samples of each pixel. Sub-electron noise is shown in three different acquisition approaches. The signal range is 6000 electrons. The readout system achieves 0.2e{e^{-}} RMS by averaging 1000 samples with MIDNA both at room temperature and at 180 Kelvin

    Exploring Perovskite Photodiodes:Device Physics and Applications

    Get PDF

    Modeling and Control of MEMS-based Multi-layered Prestressed Piezoelectric Cantilever Beam

    Full text link
    Piezoelectric materials are the preferred smart materials for sensing and actuation in the form of micro and nano-engineering structures like beams and plates. Cantilever beams play a significant role as key components in atomic force microscopy and bio and chemical sensors. Adding an active layer such as lead zirconate titanate (PZT) thin-film to form smart cantilever beams with sensing and actuation capabilities is highly desirable to facilitate miniaturization, enhance performance and functionali- ties such as enabling on-chip high-speed parallel AFM. During the micro-fabrication process, residual stresses develop in the different layers of the cantilever beam, causes initial deflection. The residual stress in the different layers of the cantilever beam and the application of voltage to the PZT thin-film affects their dynamics. This the- sis investigates the dynamic behaviour and develops a control technique and a novel charge readout circuit to improve the performance of a micro-fabricated multi-layer prestressed piezoelectric cantilever beam as an actuator and a deflection sensor. Firstly, the fabrication process of a unimorph PZT cantilever beam is explained. A low thermal budget Ultra-high vacuum e-beam evaporated polysilicon thin-film (UHVEEpoly) process is used for the fabrication of multi-layered PZT cantilever beam in d31 mode. The sharp peaks at resonant frequencies in the frequency response of the PZT cantilever beam show very little damping and a large settling time of the cantilever beam. Secondly, the dynamic behaviour of the prestressed PZT cantilever beam is in- vestigated subjected to change in driving voltage. Experimental investigations show a shift in resonant frequencies of a PZT cantilever beam. However, there is no reported mathematical model that predicts the shift in resonance frequencies of a multi-layered prestressed piezoelectric cantilever beam subjected to a change in driving voltage. This work developed a mathematical model with experimental val- idation to estimate the shift in resonance frequencies of such cantilever beams with the change in the driving voltage. A very good agreement between the model predic- tions and experimental measurements for the frequency response of the cantilever beam at different driving voltages has been obtained. A novel linear formulation has been developed to predict the shift in resonance frequencies of the PZT can- i tilever beam for a wide range of driving voltages. The formulation shows that the shift in resonance frequencies of a multi-layered prestressed piezoelectric cantilever beam per unit of applied voltage is dependent on geometric parameters and material properties. Thirdly, a robust resonant controller has been designed and implemented to re- duce the settling time of a highly vibrating PZT cantilever beam. The controller design is based on a mixed negative-imaginary, passivity, and a small-gain approach. The motivation to design a resonant controller using the above-mentioned analyti- cal framework is its bandpass nature and the use of velocity feedback, as the charge collected from a vibrating PZT cantilever beam gives the velocity information of the beam. The proposed controller design results in finite gain stability for a pos- itive feedback interconnection between two stable linear systems with a large gain and phase margin. Experimental results demonstrate that the designed resonant controller is able to effectively damp the first resonant mode of a cantilever, signifi- cantly reducing settling time from 528 ms to 32 ms. The robustness of the designed resonant controller is tested against changes in the cantilever beam dynamics due to residual stress variation and or stress variation due to driving voltage. Finally, to facilitate the miniaturization of on-chip sensors and parallel high- speed AFM, a single layer of a PZT thin-film in a cantilever beam is used as a deflection sensor and an actuator instead of bulky optical deflection sensors. A novel charge readout circuit is designed for deflection sensing by capturing the electrical charge generated due to the vibration of the PZT beam. The signal-to-noise ratio and sensitivity analysis of the readout circuit shows similar results compared to the commercially available optical deflection sensors. Our work highlights very important aspects in the dynamic behaviour and perfor- mance of a multi-layered prestressed piezoelectric cantilever beam. The agreement between the proposed theoretical formulation and experimental investigations in modeling, control design, and a novel readout circuit will provide the platform for further the development and miniaturization of microcantilever-based technologies, including on-chip parallel HS-AFM

    APPROXIMATE COMPUTING BASED PROCESSING OF MEA SIGNALS ON FPGA

    Get PDF
    The Microelectrode Array (MEA) is a collection of parallel electrodes that may measure the extracellular potential of nearby neurons. It is a crucial tool in neuroscience for researching the structure, operation, and behavior of neural networks. Using sophisticated signal processing techniques and architectural templates, the task of processing and evaluating the data streams obtained from MEAs is a computationally demanding one that needs time and parallel processing.This thesis proposes enhancing the capability of MEA signal processing systems by using approximate computing-based algorithms. These algorithms can be implemented in systems that process parallel MEA channels using the Field Programmable Gate Arrays (FPGAs). In order to develop approximate signal processing algorithms, three different types of approximate adders are investigated in various configurations. The objective is to maximize performance improvements in terms of area, power consumption, and latency associated with real-time processing while accepting lower output accuracy within certain bounds. On FPGAs, the methods are utilized to construct approximate processing systems, which are then contrasted with the precise system. Real biological signals are used to evaluate both precise and approximative systems, and the findings reveal notable improvements, especially in terms of speed and area. Processing speed enhancements reach up to 37.6%, and area enhancements reach 14.3% in some approximate system modes without sacrificing accuracy. Additional cases demonstrate how accuracy, area, and processing speed may be traded off. Using approximate computing algorithms allows for the design of real-time MEA processing systems with higher speeds and more parallel channels. The application of approximate computing algorithms to process biological signals on FPGAs in this thesis is a novel idea that has not been explored before

    Precision spectroscopy of the 2S-6P transition in atomic deuterium

    Get PDF
    Die Quantenelektrodynamik (QED) bildet die Grundlage aller anderen Quantenfeldtheorien, auf denen das Standardmodell der Teilchenphysik aufgebaut ist. Derzeit ist klar, dass unser fundamentales Naturverständnis unvollständig ist, sodass erwartet wird, dass das Standardmodell um neue Teilchen oder Wechselwirkungen verändert oder erweitert werden muss. Eine Möglichkeit, diese Grenzen der Grundlagenphysik zu erforschen, ist die Durchführung von Präzisionsmessungen. Diese Arbeit untersucht die Präzisionslaserspektroskopie von Deuterium, wo die Übergangsenergien zwischen verschiedenen Energiezuständen des an den Kern gebundenen Elektrons mit Techniken wie ultrastabilen Lasern und dem Frequenzkamm genau gemessen werden können. Aufgrund der Einfachheit der wasserstoffähnlichen Atome können ihre Energieniveaus anhand der QED-Theorie für gebundene Zustände genau berechnet werden, und mit dem Experiment mit der relativen Genauigkeit in der Größenordnung von 101210^{-12} verglichen werden. Ein solcher Vergleich zwischen Theorie und Experiment ist mit der Bestimmung von Naturkonstanten verbunden, die als Parameter in die Theorie eingehen. Erst wenn mehr unabhängige Messungen als Parameter vorliegen, kann die Theorie überprüft werden. Der Vergleich zwischen Theorie und Laser-Spektroskopie im Deuterium betrifft die Ryd-berg-Konstante RR_\infty und den Deuteronen-Ladungsradius rdr_d. Dies erfordert mindestens zwei Messungen der verschiedenen Übergangsfrequenzen, um diese Konstanten zu bestimmen, und mehr Messungen, um die Theorie zu testen. Im Gegensatz zum Wasserstoff gibt es bei Deuterium nur wenige ausreichend genaue Messungen der Übergänge. In dieser Arbeit wird die erste Untersuchung des 2S-6P-Übergangs in Deuterium vorgestellt, die mit der bestehenden Frequenzmessung des 1S-2S-Übergangs kombiniert werden kann, um RR_\infty und rdr_d zu erhalten. Zusammen mit der Messung des 2S-2P-Übergangs von myonischem Deuterium stellt diese Bestimmung einen Theorietest dar. Ein solcher Vergleich ist wichtig, um die anhaltende Diskrepanz zwischen dem Ergebnis aus myonischem Deuterium und dem Durchschnitt früherer Daten aus elektronischem Deuterium, sowie die Spannungen zwischen den jüngsten Ergebnissen aus der Wasserstoffspektroskopie, zu beleuchten. Im Gegensatz zu Wasserstoff wird die Präzisionsspektroskopie des 2S-6P-Übergangs in Deuterium durch die gleichzeitige Anregung unaufgelöster Hyperfeinstruktur-Komponenten erschwert, was zur unaufgelösten Quanteninterferenz führen kann. Diese Arbeit untersucht die möglichen systematischen Effekte, die mit dieser Komplikation verbunden sind. Zusammen mit analytischen störungstheoretischen Modellen werden Supercomputersimulationen durchgeführt, um diese Effekte zu analysieren. Es wird gezeigt, dass die Quanteninterferenz für alle 2S-nnP-Übergänge in Deuterium stark unterdrückt wird, wodurch Präzisionsmessungen dieser Übergänge möglich werden. Darüber hinaus wird ein weiterer Effekt in Deuterium im Vergleich zu Wasserstoff untersucht, der sich aus der Lichtkraft ergibt, die auf die Atome in der stehenden Welle des Spektroskopielichts wirkt. Trotz zusätzlicher Zustandsvielfalt durch die gleichzeitige Anregung unaufgelöster Hyperfeinkomponenten wird gezeigt, dass diese sogenannte ``Lichtkraftverschiebung'' mit dem gut verstandenen Effekt im Wasserstoff vergleichbar ist. Die größte Herausforderung bei der Messung des 2S-6P-Ein-Photonen-Übergangs in Deuterium ist die Doppler-Verschiebung erster Ordnung. Ein großer Teil dieser Arbeit befasst sich daher mit dem verbesserten aktiven faserbasierten Retroreflektor (AFR), der eine Technik zur Unterdrückung dieser Verschiebung darstellt. Der zentrale Teil des AFR ist der Faserkollimator, der für die Erzeugung hochwertiger gegenläufiger Laserstrahlen erforderlich ist. Die Entwicklung und Charakterisierung eines solchen Kollimators für die nahe ultraviolette Wellenlänge des 2S-6P-Übergangs ist eine der wichtigsten Errungenschaften des verbesserten AFR. Die Ergebnisse dieser Arbeit können für andere Anwendungen von Interesse sein, bei denen eine hohe Strahlqualität oder wellenfront-zurückverfolgende Strahlen wichtig sind. Darüber hinaus werden die Einschränkungen der AFR untersucht, die sich aus polarisationserhaltenden Singlemode-Fasern ergeben. Neben anderen Verbesserungen wurde eine Polarisationsüberwachung der Spektroskopielaserstrahlen implementiert. Es werden verschiedene Charakterisierungsmessungen vorgestellt, um die Leistungsfähigkeit des verbesserten AFR zu demonstrieren. Schließlich wird in dieser Arbeit eine vorläufige Messung des 2S-6P-Übergangs in Deuterium vorgestellt. Für diese Messung wurde ein neuer Kryostat in die Apparatur eingebaut, der die Stabilität des Spektroskopiesignals durch reduzierte Temperaturschwankungen verbessert. Die Erzeugung des kryogenen Deuterium-Atomstrahls wurde in Abhängigkeit von der Düsentemperatur analysiert, was eine wichtige Studie für künftige Spektroskopiemessungen darstellt. Darüber hinaus wurden für die Präzisionsmessung verschiedene systematische Effekte untersucht, darunter die Fehlausrichtung des Atomstrahls und die elektrischen Streufelder. Es wird gezeigt, dass eine Präzisionsmessung des 2S-6P-Übergangs in Deuterium mit einer ähnlichen Unsicherheit wie in Wasserstoff machbar ist. Nach der vorläufigen Unsicherheitsabschätzung kann die 2S1/2_{1/2}-6P1/2_{1/2}-Übergangsfrequenz in Deuterium auf \SI{1.7}{kHz} bestimmt werden, was einer relativen Genauigkeit von 2.3×10122.3 \times 10^{-12} entspricht. Zusammen mit der 1S-2S-Messung kann dieses Ergebnis bereits die genauesten Bestimmungen des Deuteronenradius und der Rydberg-Konstante aus dem elektronischen Deuterium ermöglichen, sodass die Unsicherheiten für die Rydberg-Konstante und den Deuteronenradius δR5×105m1\delta R_\infty \simeq 5\times 10^{-5}\,\text{m}^{-1} bzw.~\delta r_d \simeq \SI{0.002}{fm} betragen. Dieses Ergebnis bildet die Grundlage für eine zukünftige Präzisionsmessung, bei der die 2S-6P-Übergangsfrequenz mit ähnlicher Genauigkeit wie bei Wasserstoff bestimmt werden soll, was δR2×105m1\delta R_\infty \simeq 2\times 10^{-5}\,\text{m}^{-1} und \delta r_d \simeq \SI{0.0007}{fm} entsprechen würde. Der Vergleich mit dem Ergebnis von myonischem Deuterium würde es dann erlauben, die QED-Theorie für gebundene Zustände auf dem Niveau von 9×10139 \times 10^{-13} zu testen.Quantum electrodynamics (QED) forms the basis for all other quantum field theories, upon which the Standard Model of particle physics is constructed. Currently, it is clear that our fundamental understanding of nature is incomplete, such that the Standard Model is expected to be modified or extended by new particles or interactions. One way to explore these frontiers of fundamental physics is to perform precision measurements. This thesis studies the precision laser spectroscopy of deuterium, where the transition energies between different energy states of the electron bound to the nucleus can be accurately measured with techniques such as ultra-stable lasers and the frequency comb. Due to the simplicity of hydrogen-like atoms, their energy levels can be precisely calculated from bound-state QED and confronted with the experiment with the relative accuracy on the order of 101210^{-12}. Such a comparison between theory and experiment is linked to the determination of fundamental constants, which enter the theory as parameters. Only if more indepedendent measurements are available than there are parameters, the theory can be tested. The comparison between theory and laser spectroscopy in deuterium concerns the Rydberg constant RR_\infty and the deuteron charge radius rdr_d. This requires at least two different transition frequency measurements to determine those constants, and more measurements to test the theory. Contrary to hydrogen, only few accurate enough transition frequency measurements are available in deuterium. This thesis presents the first study of the 2S-6P transition in deuterium, which can be combined with the existing 1S-2S transition frequency measurement to obtain RR_\infty and rdr_d. Together with the 2S-2P transition measurement from muonic deuterium, this determination provides a theory test. Such a comparison is important to shine light on the persisting discrepancy between the result from muonic deuterium and the average of previous data from electronic deuterium, as well as tensions between the recent results from hydrogen spectroscopy. In contrast to hydrogen, precision spectroscopy of the 2S-6P transition in deuterium is complicated by the simultaneous excitation of unresolved hyperfine components, possibly leading to unresolved quantum interference. This thesis studies the possible systematic effects associated with this complication. Along with analytical perturbative models, supercomputer simulations are performed to analyze these effects. It is shown, that quantum interference is strongly suppressed for all 2S-nnP transitions in deuterium, making precision measurements of these transitions possible. Furthermore, another effect is studied in deuterium compared to hydrogen, which arises from the light force acting on the atoms in the standing wave of the spectroscopy light. Despite additional state manifolds from the simultaneous excitation of unresolved hyperfine components, it is shown that this so-called ``light force shift'' is comparable to the well understood effect in hydrogen. The main challenge of measuring the one-photon 2S-6P transition in deuterium is the first-order Doppler shift. Therefore, a large part of this thesis contributes to the improved active fiber-based retroreflector (AFR), which is a technique to suppress this shift. The central part of the AFR is the fiber collimator, which is required to produce high-quality counter-propagating laser beams. Designing and characterizing such a collimator for the near ultra-violet wavelength of the 2S-6P transition is one of the main achievements of the improved AFR. The results of this work can be of interest to other applications where a high beam quality or wavefront-retracing beams are important. Furthermore, the limitations of the AFR arising from single-mode polarization-maintaining fibers are investigated. Along with other improvements, a polarization monitor of the spectroscopy laser beams has been implemented. Various characterization measurements are presented to demonstrate the performance of the improved AFR. Finally, this thesis presents a preliminary measurement of the 2S-6P transition in deuterium. For this measurement, a new cryostat has been installed in the apparatus, which improves the stability of the spectroscopy signal due to reduced temperature fluctuations. The cryogenic deuterium atomic beam generation has been analyzed in dependence on the nozzle temperature, which is an important study for future spectroscopy measurements. Furthermore, for the precision measurement different systematic effects have been investigated, including the atomic beam misalignment and the stray electric fields. It is demonstrated that a precision measurement of the 2S-6P transition in deuterium with a similar uncertainty than in hydrogen is feasible. According to the preliminary uncertainty budget, the 2S1/2_{1/2}-6P1/2_{1/2} transition frequency in deuterium can be determined to \SI{1.7}{kHz}, which corresponds to 2.3×10122.3 \times 10^{-12} relative accuracy. Together with the 1S-2S measurement, already this result can enable the most accurate determinations of the deuteron radius and the Rydberg constant from the electronic deuterium with the uncertainties on the Rydberg constant and the deuteron radius of δR5×105m1\delta R_\infty \simeq 5\times 10^{-5}\,\text{m}^{-1} and \delta r_d \simeq \SI{0.002}{fm}, respectively. This result sets the stage for a future precision measurement, where the 2S-6P transition frequency is expected to be determined with the similar accuracy as in hydrogen, which would correspond to δR2×105m1\delta R_\infty \simeq 2\times 10^{-5}\,\text{m}^{-1} and \delta r_d \simeq \SI{0.0007}{fm}. The comparison to the result from muonic deuterium would then allow to test bound-state QED at the level of 9×10139 \times 10^{-13}
    corecore