A5018554987- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Scientific Measurement and Uncertainty Evaluation
- Geophysics and Sensor Technology
- Mechanical and Optical Resonators
- Geophysics and Gravity Measurements
- Pulsars and Gravitational Waves Research
- Quantum Mechanics and Applications
- Cosmology and Gravitation Theories
- Experimental and Theoretical Physics Studies
- Radioactive Decay and Measurement Techniques
- Quantum Electrodynamics and Casimir Effect
- Quantum optics and atomic interactions
- Quantum and electron transport phenomena
- Advanced Thermodynamics and Statistical Mechanics
- Relativity and Gravitational Theory
- Physics of Superconductivity and Magnetism
- Quantum, superfluid, helium dynamics
- Dark Matter and Cosmic Phenomena
- Quantum Information and Cryptography
- Statistical and numerical algorithms
- Advanced MEMS and NEMS Technologies
- Advanced Electrical Measurement Techniques
- Noncommutative and Quantum Gravity Theories
Huazhong University of Science and Technology
2015-2024
Wuhan Institute of Technology
2022-2024
Hebei GEO University
2021
University of Surrey
2020
Instituto de Ciencias Agrarias
2020
Anqing City Hospital
2019
State Grid Nanjing Power Supply Company (China)
2019
We present an ultrahigh-sensitivity gravimeter based on ${}^{87}$Rb atom interferometer using stimulated Raman transitions. Compared with our previous work, a two-dimensional magneto-optical trap is added in the new to increase number and improve detection signal-to-noise ratio, better optical phase-locked loop system used reduce phase noise of beams. Benefiting from these efforts excellent performance active vibration isolator, short-term sensitivity about 4.2...
We report a test of the universality free fall (UFF) related to spin-gravity coupling effects by comparing gravity acceleration $^{87}$Rb atoms in $m_F=+1$ versus that $m_F=-1$, where corresponding spin orientations are opposite. A Mach-Zehnder-type atom interferometer is exploited sequentially measure these two sublevels, and resultant E$\rm{\ddot{o}}$tv$\rm{\ddot{o}}$s ratio determined this work ${\eta_S} =(-0.2\pm1.5)\times 10^{-5}$. The using or $m_F=-1$ highly sensitive magnetic field...
A rotating torsion balance method is used to detect the product of photon mass squared and ambient cosmic vector potential A(e). The signal modulated by ensure effectiveness detection for all possible orientations potential. influences sidereal disturbances environment are also removed virtue this modulation method. experimental result shows micro (2)(gamma)A(e)<1.1 x 10(-11) T m/m(2), with (-1)(gamma) as characteristic length associated mass. If A(e) 10(12) m due cluster level fields, we...
We report a gravity gradiometer composed of two atom interferometers which are simultaneously locked to the respective fringe center by feedback control Raman laser phase and magnetic field gradient. Compared with conventional full-fringe recording method, this dual-fringe-locking strategy is capable increasing sampling rate improving sensitivity for gradient measurements. Meanwhile, it retains intrinsic advantage rejecting common mode noises gradiometers. A short-term $670...
This study reports a significant result in atom interferometry, specifically for gravity measurements: an achieved sensitivity of $2.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}$ m/s${}^{2}$ per shot, which advances the state art by about factor two. Integrating 2000 s, resolution here is $8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$ m/s${}^{2}$, equivalent to effect produced 60-kg person 2 m away. Based on such extremely sensitive and stable measurements, test...
A cold rubidium atom fountain interferometry gravimeter with an active vibration isolator is demonstrated. The natural resonance frequency of the 0.016 Hz, and vertical noise greatly reduced by a factor 100 from 0.1 to 1 Hz. After substantial suppression noise, reaches sensitivity ${5.5\ifmmode\times\else\texttimes\fi{}10}^{\ensuremath{-}8}$ g/Hz${}^{1/2}$. We measured local gravitational acceleration $g$ this sensitive resolution ${6.5\ifmmode\times\else\texttimes\fi{}10}^{\ensuremath{-}9}$...
The Newtonian gravitational constant
Abstract Neutral atomic tweezer arrays have become a promising platform for quantum computation, which possess rich degrees of freedom (DoFs) as an important resource encoding information. We explore the DoF in ladder-shaped array and propose scheme high-dimensional universal computation. This encodes qubits to two single atom, namely motional (Mo) site-occupation (SO) DoFs, allows one atom carry results two-layer qubit architecture. The single-qubit rotational gates on Mo- SO-qubits, well...
The magnetic field gradient has been measured with an atom interferometer using the sublevels of $^{87}\mathrm{Rb}$ atoms. Doppler-insensitive measurement effectively eliminates contribution from gravity and background vibration noise, differential also can reject some systematic errors. A resolution $300$ pT/mm demonstrated a $90$-s integration time spatial $1.4$ mm. gradiometer was then used to measure in ultrahigh-vacuum environment. technique will be very useful subtract error arising...
A compact laser system for a portable 87Rb atom interferometry gravimeter has been demonstrated in this work. This is based on frequency doubling of single seed at the wavelength 1560 nm. The controlled by digital unit with an analog feedback circuit. By using control method, can be shifted over 1 GHz. Based Raman locked F = 3 → F′ 4 transition 85Rb atoms. Moreover, sideband and repumping are generated phase modulator, it generate different frequencies to meet requirements typical...
Abstract The Newtonian gravitational constant G , which is one of the earliest fundamental constants introduced by human beings, plays an important role in cosmology, astrophysics, geophysics, metrology, and so on. In spite measurement having a relative longer history more than 200 results been obtained during past years, still remains least precisely known among all physical up to now. Over three decades, many experimental physicists devoted themselves with various methods resulted dozen...
The Newtonian gravitational constant G is determined by means of a high-Q torsion pendulum and the time-of-swing method, in which period altered presence two 6.25-kg stainless steel cylinders. nonlinear fitting method used to extract frequencies from angle-time data pendulum. resulting value...
We have investigated Lorentz violation through analyzing tides-subtracted gravity data measured by superconducting gravimeters. At the level of precision gravimeters, we brought up and resolved an existing issue accuracy due to unaccounted local tidal effects in previous solid-earth model used. Specifically, taken tides into account with a brand new first-principles ocean included, as well removed potential bias from using worldwide array 12 Compared test more accurate competitive bound on...
An ultra-low frequency active vibration isolator, simultaneously suppressing three-dimensional noise, is demonstrated experimentally. The equivalent natural period of the isolator 100 s and 12 for vertical horizontal direction, respectively. noise in direction about 50 times reduced during 0.2 2 Hz, 5 other two orthogonal directions same range. This designed atom gravimeters, especially suitable gravimeter whose sensitivity limited by couplings.
The effect of wavefront aberrations is one the most important systematic errors in atom interferometers and limits accuracy precision gravimeters. A detailed theoretical analysis this presented, a method for observing proposed demonstrated experiment. In addition, with method, surface quality optical elements Raman system was measured rms resolution $0.01\ensuremath{\lambda}$.
Developments of the micro-Gal level gravimeter based on atom interferometry are reviewed, and recent progress results our group also presented. Atom interferometric gravimeters have shown high resolution accuracy for gravity measurements. This kind quantum sensor has excited world-wide interest both practical applications fundamental research.
We perform a precision atom interferometry experiment to test the universality of free fall. Our employs Bragg interferometer with 87 Rb atoms either in hyperfine state <?CDATA $\left|F=1,{m}_{F}=0\right.\rangle $?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mfenced close="〉" open="|"> <mml:mrow> <mml:mi>F</mml:mi> <mml:mo>=</mml:mo> <mml:mn>1</mml:mn> <mml:mo>,</mml:mo> <mml:msub> <mml:mi>m</mml:mi> </mml:mrow> </mml:msub> <mml:mn>0</mml:mn>...
Eccentricities of the mass center from geometric two cylindrical source masses used in HUST-99 measurement Newtonian gravitational constant $G$ are determined by means an electronic balance. Considering a linear density distribution as well effect air buoyancy, our value should be revised to $6.6723(9)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}\text{ }\text{ }{\mathrm{m}}^{3}\text{ }{\mathrm{kg}}^{\ensuremath{-}1}\text{ }{\mathrm{s}}^{\ensuremath{-}2}$, which is 0.036% larger...
As part of a program to determine the gravitational constant G using multiple independent methods in same laboratory, an atom gravity gradiometer is being developed. The designed with two magneto-optical traps ensure both fast simultaneous launch atomic clouds and optimized configuration source masses. Here, design measurement by interferometry detailed, experimental setup reported. A preliminary sensitivity 3 × 10−9 g/Hz differential acceleration obtained, which corresponds 99 E/Hz (1 E =...
As a novel instrument for measuring absolute gravity, the atom gravimeter has shown high sensitivity and stability in past three decades. In this work, we report car-based portable whose is at level of 1.9mGal/Hz (1 Gal = 0.01 m/s2) both lab outdoor measurements. Its resolution can reach 30 μGal within an integration time 10 000 s when located quiet place. During four months gravity observation, there no drift measurement result, showing that competitive advantage long term stability. By...
A thrust stand is developed for testing micro-Newton level thrusters on the ground. The composed of a compound pendulum that symmetrically suspended by two thin beryllium copper strips, and it precisely calibrated gravity. stiffness can be adjusted in 3 orders magnitude counterweight. When larger than 1 Nm/rad, demonstrates fast response to thrust. measured range reaches 1000 μN, noise less 0.1 μN/Hz within mHz-1 Hz. To calibrate resolution stand, an electrostatic force applied with...
Abstract Atom interferometry provides an important method of high-precision absolute gravity measurement. As gravimeters, various systematic errors atom gravimeters have been identified and evaluated. Here a comprehensive evaluation for transportable gravimeter Huazhong University Science Technology-Quantum Gravimeter (HUST-QG) is presented. HUST-QG exhibited short-term sensitivity 24 μGal Hz −1/2 combined uncertainty 3 μGal. The operation measurements during the 10th International...
Precisely measuring the magnetic-field gradient within a vacuum chamber is important for many precision experiments and can be realized by atom interferometry using magnetically sensitive sublevels at different times to make differential measurement, which had been demonstrated in our previous work. In this paper, we demonstrate method measure means of two simultaneously operated interferometers double atomic fountains. By virtue simultaneous measurement reject common-mode noise, resolution...