A5043385985- Advanced Frequency and Time Standards
- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Quantum optics and atomic interactions
- Spectroscopy and Laser Applications
- Advanced Fiber Laser Technologies
- Laser Design and Applications
- Photorefractive and Nonlinear Optics
- Scientific Measurement and Uncertainty Evaluation
- Solid State Laser Technologies
- Photonic and Optical Devices
- Seismic Waves and Analysis
- Geophysics and Gravity Measurements
- Laser-Matter Interactions and Applications
- Semiconductor Lasers and Optical Devices
- Quantum Information and Cryptography
- Metamaterials and Metasurfaces Applications
- Photonic Crystals and Applications
- Mechanical and Optical Resonators
- Geophysics and Sensor Technology
- Geophysical and Geoelectrical Methods
- Atomic and Molecular Physics
- Photochemistry and Electron Transfer Studies
- Pulsars and Gravitational Waves Research
- Plasmonic and Surface Plasmon Research
University of Birmingham
2016-2024
Birmingham City University
2024
University College London
2020
Imperial College London
2015-2016
University of Florence
2010-2014
National Tsing Hua University
2004-2013
Istituto Nazionale di Fisica Nucleare, Sezione di Firenze
2012-2013
Abstract We propose in this White Paper a concept for space experiment using cold atoms to search ultra-light dark matter, and detect gravitational waves the frequency range between most sensitive ranges of LISA terrestrial LIGO/Virgo/KAGRA/INDIGO experiments. This interdisciplinary experiment, called Atomic Experiment Dark Matter Gravity Exploration (AEDGE), will also complement other planned searches exploit synergies with wave detectors. give examples extended sensitivity matter offered...
We evaluate the sensitivity of a dual cloud atom interferometer to measurement vertical gravity gradient. study influence most relevant experimental parameters on noise and long term drifts. Results are also applied case doubly differential measurements gravitational signal from local source masses. achieve short-term $3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$ g/$\sqrt{\text{Hz}}$ acceleration, limited by quantum projection instrument. Active control critical allows us reach...
Abstract The sensing of gravity has emerged as a tool in geophysics applications such engineering and climate research 1–3 , including the monitoring temporal variations aquifers 4 geodesy 5 . However, it is impractical to use cartography resolve metre-scale underground features because long measurement times needed for removal vibrational noise 6 Here we overcome this limitation by realizing practical quantum gradient sensor. Our design suppresses effects micro-seismic laser noise, thermal...
A metasurface optical chip allows the generation of cold atoms with a single-beam magneto-optical trap (MOT) system.
The high precision and scalable technology offered by atom interferometry has the opportunity to profoundly affect gravity surveys, enabling detection of features either smaller size or greater depth. While such systems are already starting enter into commercial market, significant reductions required in order reach size, weight power conventional devices. In this article, potential for based gravimetry is assessed, suggesting that key resides within development gradiometry sensors enable...
We demonstrate a method to measure the gravitational acceleration with dual cloud atom interferometer; use of simultaneous interferometers reduces effect seismic noise on gravity measurement. At same time, apparatus is capable accurate measurements vertical gradient. The ability determine and gradient simultaneously instrument opens interesting perspectives in geophysical applications.
A frequency doubled I/Q modulator based optical single-sideband (OSSB) laser system is demonstrated for atomic physics research, specifically atom interferometry where the presence of additional sidebands causes parasitic transitions. The performance OSSB technique and spectrum after second harmonic generation are measured analyzed. removed with better than 20 dB suppression, influence transitions upon stimulated Raman at varying spatial positions shown to be beneath experimental noise. This...
Gravitational Waves (GWs) were observed for the first time in 2015, one century after Einstein predicted their existence. There is now growing interest to extend detection bandwidth low frequency. The scientific potential of multi-frequency GW astronomy enormous as it would enable obtain a more complete picture cosmic events and mechanisms. This unique entirely new opportunity future astronomy, success which depends upon decisions being made on existing infrastructures. prospect combining...
We here present a high sensitivity gravity-gradiometer based on atom interferometry.In our apparatus, two clouds of laser-cooled rubidium atoms are launched in fountain configuration and interrogated by Raman interferometry sequence to probe the gradient gravity field.We recently implemented high-flux atomic source newly designed lasers system instrument set-up.We discuss applications towards precise determination Newtonian gravitational constant G.The long-term stability signal-to-noise...
Abstract It is usually considered that the spectrum of an optical cavity coupled to atomic medium does not exhibit a normal-mode splitting unless system satisfies strong coupling condition, meaning Rabi frequency coherent exceeds decay rates atom and excitations. Here we show this need be case, but depends on way in which probed. Measurements reflection probe laser from input mirror overdamped reveal avoided crossing observed when driving atoms directly measuring Purcell-enhanced emission....
This paper reports on a detailed performance characterization of recently developed optical single-sideband (OSSB) laser system based an IQ modulator and second-harmonic generation for rubidium atom interferometry experiments. The measured is used to evaluate the noise contributions this OSSB when it applied drive stimulated Raman transitions in $^{87}$Rb precision measurements gravitational acceleration. suppresses unwanted sideband components, but additional phase shift compensation needs...
Dibenzoterrylene (DBT) molecules within a crystalline anthracene matrix show promise as quantum emitters for controlled, single photon production. We present the design and construction of chamber in which we reproducibly grow doped crystals optical quality that are several mm across few μm thick. demonstrate control DBT concentration over range 6–300 parts per trillion these stable single-photon emitters. interpret our data with simple model provides some information on vapour pressure DBT.
We have developed a widely tunable mid-infrared difference frequency generation (DFG) source by mixing ~ 1 W Ti:sapphire laser and 6 Nd:YAG beams in 50-mm MgO-doped long periodically poled lithium niobate (MgO:PPLN). The power of the DFG is > 2 mW over tuning range 2.66-4.77 μm its free-running linewidth about 100 kHz. Combining various stabilisation schemes for laser, can be precisely controlled. Besides, determined better than 12 kHz measuring using an optical comb. Two high resolution...
We have precisely measured the frequencies of 12 transitions ${\ensuremath{\nu}}_{2}$ fundamental band ${\mathrm{H}}_{3}^{+}$ molecular ion. Their absorption spectra are observed using a precision tunable difference frequency generation (DFG) source and direct current discharge tube with ion concentration modulation scheme. Accurate calibration DFG by an optical comb iodine-stabilized laser enables us to measure transition accuracy one order magnitude better than that achieved in previous results.
The UK National Quantum Technology Hub in Sensors and Metrology is one of four flagship initiatives the Program. As part a 20-year vision it translates laboratory demonstrations to deployable practical devices, with game-changing miniaturized components prototypes that transform state-of-the-art for quantum sensors metrology. It brings together experts from Universities Birmingham, Glasgow, Nottingham, Southampton, Strathclyde Sussex, NPL currently links over 15 leading international...
The measurement of the absolute frequencies $2S\ensuremath{\rightarrow}3S$ atomic lithium is reported. To reduce systematic effects, we employed a frequency-comb-stabilized excitation laser, weakly collimated beam, and cascading $2P\ensuremath{\rightarrow}2S$ 670 nm fluorescence as signal. transition frequencies, including two isotopes (${}^{6,7}\mathrm{Li}$), were measured to an accuracy $<\phantom{\rule{0.16em}{0ex}}330\phantom{\rule{4.pt}{0ex}}\text{kHz}$. In comparison with previous...
We proposed the European Laboratory for Gravitation and Atom-interferometric Research (ELGAR), an array of atom gradiometers aimed at studying space-time gravitation with primary goal observing gravitational waves (GWs) in infrasound band a peak strain sensitivity $3.3 \times 10^{-22}/\sqrt{\text{Hz}}$ 1.7 Hz. In this paper we detail main technological bricks large scale detector emphasis research pathways to be conducted its realization. discuss site options, optics, source requirements...
One of the most precisely determined upper limits for electron electric dipole moment (EDM) is set by thallium (Tl) atomic beam experiment. way to enhance sensitivity setup laser cool Tl atoms reduce EDM-like phase caused E$\ifmmode\times\else\texttimes\fi{}$v effect. In this report, a cooling scheme based on $6{P}_{3/2}(F=2)\ensuremath{\leftrightarrow}6{D}_{5/2}({F}^{\ensuremath{'}}=3)$ transition in proposed. The absolute frequency measurement nearly closed-cycle was performed an...
A 1071 nm laser using Nd:GdVO 4 as the gain medium is demonstrated. volume Bragg grating (VBG) with a reflection central wavelength at 1069.8 was used. The operated in CW mode. output range could exceed 1.3 by tuning VBG temperature. Single longitudinal mode operation achieved an power larger than 100 mW simple linear cavity setup. brief discussion about thermal effect also presented.
We experimentally investigated the resonance effect of planar metallic split ring resonators (SRRs) in far-infrared region (FIR) (∼10.6 µm). Experimental results indicated that they exhibit around 10.6 µm, implying negative permeability FIR region. Furthermore, ratio effective dimensions SRR cell and wavelength incident beam was 1 which suggested a wide scale independence. This size tolerance is useful realizing meta-materials with indices refraction optical domain.
A Nd:GdVO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> laser was built with a volume Bragg grating as the fold mirror, wavelength selector and spectral narrowing element. Over 2 nm tuning centered at 1063.39 achieved by angular tuning.
This paper reports on the development of a transportable high data rate quantum absolute gravimeter for gravity map matching navigation. Its target sensitivity is 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-7</sup> g/√ Hz at 100 with stability xmlns:xlink="http://www.w3.org/1999/xlink">-9</sup> g over month. The design issues, analysis and an evaluation noises are discussed.
We have developed two kinds of ultra-flexible film-like liquid crystal display, pixel-isolated twist nematic and polymer encapsulated displays. By the aids wall in thin variation cell gap bending condition is greatly reduced. They are good candidates for rollable flexible display due to excellent flexibility. In this work, first time that electro-optical properties reliability a after test investigated, application limit investigated.
Cold-atom systems are rapidly advancing in technical maturity and have, many cases, surpassed their classical counterparts, becoming a versatile tool that is used variety of fundamental research applications [...]
<title>Abstract</title> The numerical model has been developed for atomic ladder (cascade) systems, which proves to be suitable Rydberg RF sensors.This is designed with the capability extended N-level non-thermal systems ease. adaptability of this sensors validated by comparing its results those earlier reported experiments. here provides a good approximation experimental results. Thus, such dynamic can useful quantum technologists in designing, optimising, and developing RF-based...