• Journal of the Optical Society of Korea
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• 제13권2호
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• pp.223-226
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• 2009

A Magneto-Optical Trap (MOT) for $^{87}Rb$ atoms near the surface of a dielectric coated mirror at the top of a small $20{\times}25{\times}40\;mm^3$ cell has been observed. Two beams of $3.3\;mW/cm^2$ were used for optical cooling and an anti-Helmholtz magnetic field with a spatial gradient of 9.1 G/cm was used for magnetic trapping. The thickness of the mirror coated on a cover glass was less than $100{\mu}m$. The mirror covered the top of a cell and the atom-chip was located outside the vacuum in order to exploit the long life time of the mirror and easy operation of the chip. The trapping position was found 5 mm beneath the mirror surface. The number of trapped atoms was roughly $3{\times}10^7$ atoms and the temperature was approximately a few tens mK. In this paper, we describe the construction of the mirror-MOT in detail.

• Journal of the Optical Society of Korea
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• 제9권3호
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• pp.87-91
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• 2005

The strontium magneto optical trap followed by a Zeeman slower has been demonstrated. The isotope selective characteristics of the trap have been investigated. The fluorescence spectrum of the MOT was compared with those of other high resolution spectroscopic methods. The red detuned deflection beam is also considered for a more selective spectrum.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 하계학술발표회
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• pp.74-75
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• 2000

The past few decades have witnessed the development of very robust technique, known as magneto-optical trap(MOT), for cooling and trapping of neutral atoms using lasers and magnetic fields. This technique can easily produce cooled atoms to a temperature range of nano-kelvin $s^{(1)}$ . These laser cooled and trapped atoms have found applications in various fields, such as ultrahigh resolution spectroscopy, precision atomic clocks, very cold atomic collision physics, Bose-Einstein Condensation, the Atom laser, etc. Particularly, a few isolated atoms of very low temperature are needed in the cavity QED studies in the optical regime. One can obtain such atoms from a MOT using the atomic fountain technique. The widely used technique for atomic fountain is, first to cool and trap the neutral atoms in MOT. And then launch them in the vertical (1, 1, 1) direction with respect to cooling beams, using moving molasses technique. Recently, this technique combined with the cavity-QED has opened an active area of basic research. This way atoms can be strongly coupled to the optical radiation in the cavity and leads to various new effects. Trapping of single atom after separating it from MOT in the high Q-optical cavity is actively initiated presentl $y^{(2.3)}$. This will help to sharpen our understanding of atom-photon interaction at quantum level and may lead to the development of single-atom laser. Our efforts to develop an $^{85}$ Rb-atomic fountain is in progress. (omitted)

• 한국광학회지
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• 제11권4호
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• pp.221-226
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• 2000

MOT에 포획된 원자 구름의 분포가 포획광의 편광, 어긋난 정렬에 따라 구형, 막대형, 고리형, 가운데 구를 포함한 고리형, 구-구형, 구-고리형 등으로 다양하게 변하는 것을 관측하였다. 이는 포획광의 어긋난 정렬 등에 의한 좌표의존 비대칭 광압(Coordinate-dependent asymmetry radiation force ; CDARF)으로 설명할 수 있었다. 루비듐-87 원자의 S1/2(F=2), P3/2(F=3)준위에 축퇴된 제만 부준위에 대하여 제만 주파수 이동, 자기장과 포획광 방향에 따른 전이 확률, 편광에 따른 전이 확률, 레이저광의 편광, 레이저 광의 공간 분포 등을 고려하여 가능한 정확한 운동방정식을 세우고, 이를 풀어 다양한 형태의 원자구름 분포를 설명하였다.