Browsing by Author "Huang, MS"

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A calcium vapor cell for atomic spectroscopy
(2002-11-01)
Huang, MS
;
Lu, MH
;
Shy, JT
;
物理研究所
;
光電工程學系
A calcium vapor cell used in laser spectroscopy usually suffers from calcium coating on the cell windows. To solve the problem, we add two mirrors in the cell to reflect the laser beam, then the calcium will coat on these mirrors instead of on the windows. Calcium coating degrades the reflectivity of the mirrors at the beginning, but the mirrors become calcium mirrors after a certain period of coating and their reflectivity will not change by further calcium coating. Using this cell in a conventional saturated-absorption spectroscopy, the observed saturated-absorption peak at 657 nm is about 2.4% of the probe beam power and its linewidth is below 300 kHz. Therefore, a portable secondary calcium-wavelength standard at 657 nm having an accuracy better than 1x10(-11) is possible. In addition, our cell has a continuous working time longer than 3 d and it can be easily extended to 10 d. (C) 2002 American Institute of Physics.
Frequency stabilizations of GaN blue diode laser
(2001)
Chang, F
;
Lee, HY
;
Huang, MS
;
Wang, SC
;
光電工程學系
High sensitivity bulk electro-optic modulator field sensor for high voltage environments
(2004-12-01)
Huang, MS
;
Lu, MH
;
Shy, JT
;
光電工程學系
;
Department of Photonics
An optical electric field sensor is an effective instrument for surveying the electric or magnetic field around a high voltage electrical system. A Mach-Zender interferometer type modulator is generally used in this kind of sensor. The sensor has good sensitivity to electric or magnetic fields, but an unexpected high field could easily destroy the modulator owing to its short electrode separation. A bulk modulator usually has long separation between the two electrodes, which can prevent modulator breakdown, but its sensitivity is usually worse than the Mach-Zender interferometer type sensor. To solve this problem, a Fabry-Perot cavity is used to improve the sensitivity of the bulk modulator type sensor. This work also discusses the optimization of the sensor sensitivity. When the sensor works on the point where a cavity resonance has maximal slope, the proposed sensor has approximately the same sensitivity for sensing a field as the Mach-Zender interferometer type sensor. (C) 2004 American Institute of Physics.
Novel method to stabilize a laser wavelength unaffected by Fabry-Perot etalon angle drift
(2004-05-01)
Huang, MS
;
Lu, MH
;
Shy, JT
;
光電工程學系
;
Department of Photonics
A laser with its wavelength stabilized to a Fabry-Perot etalon has many industrial applications. An ideal error signal for laser stabilization is the dispersion-like signal generated without wavelength modulation. We present a technique, by which the error signal is generated by the difference of two resonance peaks of a Fabry-Perot etalon. A laser beam is split into two beams, which pass through an etalon with a small optical path length difference to generate two partially overlapped resonance peaks. Subtracting one peak from the other yields a dispersion-like error signal. The zero crossing of the differential signal is insensitive to the angle drift of the etalon if the incident angles of the two laser beams are nearly equal but with opposite sign. (C) 2004 Society of Photo-Optical Instrumentation Engineers.