Demonstration of a MOT in a sub-millimeter membrane hole

AbstractWe demonstrate the generation of a cold-atom ensemble within a sub-millimeter diameter hole in a transparent membrane, a so-called “membrane MOT”. With a sub-Doppler cooling process, the atoms trapped by the membrane MOT are cooled down to 10 $$\upmu$$ μ K. The atom number inside the unbridged/bridged membrane hole is about $$10^4$$ 10 4 to $$10^5$$ 10 5 , and the $$1/e^2$$ 1 / e 2 -diameter of the MOT cloud is about 180 $$\upmu$$ μ m for a 400 $$\upmu$$ μ m-diameter membrane hole. Such a membrane device can, in principle, efficiently load cold atoms into the evanescent-field optical trap generated by the suspended membrane waveguide for strong atom-light interaction and provide the capability of sufficient heat dissipation at the waveguide. This represents a key step toward the photonic atom trap integrated platform (ATIP).

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Membrane MOT: Trapping Dense Cold Atoms in a Sub-Millimeter Diameter Hole of a Microfabricated Membrane Device

10.21203/rs.3.rs-107899/v1 ◽

2020 ◽

Author(s):

Jongmin Lee ◽

Grant Biedermann ◽

John Mudrick ◽

Erica Douglas ◽

Yuan-Yu Jau

Keyword(s):

Integrated Circuits ◽

Cold Atoms ◽

Optical Trap ◽

Cold Atom ◽

Hole Diameter ◽

Beam Diameter ◽

Atom Number ◽

Diameter Hole ◽

Doppler Cooling ◽

Scaling Rule

Abstract We present a demonstration of keeping a cold-atom ensemble within a sub-millimeter diameter hole in a transparent membrane.Based on the effective beam diameter of the magneto-optical trap (MOT) given by the hole diameter (d = 400 μm), we measurean atom number that is 105 times higher than the predicted value using the conventional d6 scaling rule. Atoms trapped bythe membrane MOT are cooled down to 10 μK with sub-Doppler cooling. Such a device can be potentially coupled to thephotonic/electronic integrated circuits that can be fabricated in the membrane device representing a step toward the atom trapintegrated platform.

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A large-scale cold atom source in an integrating sphere

Modern Physics Letters B ◽

10.1142/s0217984914501164 ◽

2014 ◽

Vol 28 (14) ◽

pp. 1450116 ◽

Cited By ~ 1

Author(s):

Ben-Chang Zheng ◽

Hua-Dong Cheng ◽

Yan-Ling Meng ◽

Peng Liu ◽

Xiu-Mei Wang ◽

...

Keyword(s):

Large Scale ◽

Cold Atoms ◽

Signal To Noise Ratio ◽

Atomic Clock ◽

Cold Atom ◽

Integrating Sphere ◽

Cooling Power ◽

Atom Number ◽

Atom Source ◽

Good Signal

An integrating sphere with a diameter of 10 cm is developed for cooling atoms. The maximum number of 2 × 1010 cold atoms is obtained from a background vapor with 220 mW cooling laser power. The cold atom number can be increased by further increasing the cooling power. Such cold atom source would have potential use for Raman–Ramsey atomic clock with good signal-to-noise ratio (SNR).

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Atom number calibration in absorption imaging at very small atom numbers

Open Physics ◽

10.2478/s11534-012-0108-x ◽

2012 ◽

Vol 10 (5) ◽

Cited By ~ 1

Author(s):

Gregory Konstantinidis ◽

Melina Pappa ◽

Gustav Wikström ◽

Paul Condylis ◽

Daniel Sahagun ◽

...

Keyword(s):

Fluorescence Imaging ◽

Optical Trap ◽

Cold Atom ◽

Single Atom ◽

Absolute Calibration ◽

Accurate Information ◽

Atom Number ◽

Absorption Imaging ◽

Small Atom ◽

Dark Ground

AbstractCold atom experiments often use images of the atom clouds as their exclusive source of experimental information. The most commonly used technique is absorption imaging, which provides accurate information about the shapes of the atom clouds, but requires care when seeking the absolute atom number for small atom samples. In this paper, we present an independent, absolute calibration of the atom numbers. We directly compare the atom number detected using dark-ground imaging to the one observed by fluorescence imaging of the same atoms in a magneto-optical trap. We normalise the signal using single-atom resolved fluorescence imaging. In order to be able to image the absorption of the very low atom numbers involved, we use diffractive dark-ground imaging as a novel, ultra-sensitive method of in situ imaging for untrapped atom clouds down to only 100 atoms. We demonstrate that the Doppler shift due to the acceleration of the atoms by the probe beam has to be taken into account when measuring the atom-number.

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Towards a compact, optically interrogated, cold-atom microwave clock

Advanced Optical Technologies ◽

10.1515/aot-2020-0022 ◽

2020 ◽

Vol 9 (5) ◽

pp. 297-303

Author(s):

Rachel Elvin ◽

Michael W. Wright ◽

Ben Lewis ◽

Brendan L. Keliehor ◽

Alan Bregazzi ◽

...

Keyword(s):

Cold Atoms ◽

Optical Trap ◽

Cold Atom ◽

Free Fall ◽

Coherent Population Trapping ◽

Short Term ◽

State Splitting ◽

Noise Limit ◽

Atomic Ground State ◽

Population Trapping

AbstractA compact platform for cold atoms opens a range of exciting possibilities for portable, robust and accessible quantum sensors. In this work, we report on the development of a cold-atom microwave clock in a small package. Our work utilises the grating magneto-optical trap and high-contrast coherent population trapping in the lin$\perp $lin polarisation scheme. We optically probe the atomic ground-state splitting of cold 87Rb atoms using a Ramsey-like sequence whilst the atoms are in free-fall. We have measured a short-term fractional frequency stability of $5{\times}{10}^{-11}/\sqrt{\tau }$ with a projected quantum projection noise limit at the ${10}^{-13}/\sqrt{\tau }$ level.

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Cold atom interferometry for inertial sensing in the field

Advanced Optical Technologies ◽

10.1515/aot-2020-0026 ◽

2020 ◽

Vol 9 (5) ◽

pp. 221-225

Author(s):

Ravi Kumar ◽

Ana Rakonjac

Keyword(s):

High Precision ◽

Cold Atoms ◽

Cold Atom ◽

Atom Interferometry ◽

Precision Measurements ◽

Inertial Sensing ◽

Fundamental Physics ◽

Recent Developments ◽

Resource Exploration ◽

Atom Interferometers

AbstractAtom interferometry is one of the most promising technologies for high precision measurements. It has the potential to revolutionise many different sectors, such as navigation and positioning, resource exploration, geophysical studies, and fundamental physics. After decades of research in the field of cold atoms, the technology has reached a stage where commercialisation of cold atom interferometers has become possible. This article describes recent developments, challenges, and prospects for quantum sensors for inertial sensing based on cold atom interferometry techniques.

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