The use of saturation dip absorption in microwave spectroscopy and in microwave frequency stabilization

1969 ◽  
Vol 47 (21) ◽  
pp. 2431-2433 ◽  
Author(s):  
C. C. Costain
Keyword(s):  
Laser Field ◽  
Microwave Frequency ◽  
Frequency Stabilization ◽  
Microwave Spectroscopy ◽  
Absorption Lines ◽  
Microwave Frequencies

An experiment is described which shows that the saturation dip technique (often termed the Lamb dip, in the laser field) can be used at microwave frequencies to identify the centers of absorption lines very precisely. The use of this technique in microwave spectroscopy is illustrated and the possibility of using this technique to stabilize oscillators is discussed.

Frequency stabilization of a Ho:Tm:YLF laser to absorption lines of carbon dioxide

2000 ◽  
Vol 39 (21) ◽  
pp. 3664 ◽  
Author(s):  
Grady J. Koch ◽  
Amin N. Dharamsi ◽  
Colleen M. Fitzgerald ◽  
John C. McCarthy
Keyword(s):  
Carbon Dioxide ◽  
Frequency Stabilization ◽  
Absorption Lines

The Effect of Drop-Size Distribution Variability on Radiometric Estimates of Rainfall Rates for Frequencies from 3 to 10 GHz

1991 ◽  
Vol 30 (7) ◽  
pp. 1025-1033 ◽  
Author(s):  
A. R. Jameson
Keyword(s):  
Absorption Coefficient ◽  
Size Distribution ◽  
Drop Size ◽  
Radiative Transfer Equation ◽  
Microwave Frequency ◽  
Drop Size Distribution ◽  
Rainfall Rate ◽  
Field Of View ◽  
Ice Clouds ◽  
Microwave Frequencies

Abstract The substantial upwelling microwave radiation emitted by rain, as well as the relative simplicity of radiometers, guarantees their continuing important role in measuring rain from space. However, for frequencies greater than around 20 GHz, ice clouds overlying rain often scatter much of the upwelling radiation out of the field of view. In addition, at these frequencies raindrops scatter so well that oven when a few more are added to an already low concentration of drops, the additional drops actually scatter away more radiation than they contribute to the field of view. Because of these two effects, the direct measurement of rainfall rate at high microwave frequencies using upwelling radiation is restricted to low rainfall rates. In contrast, from 3 to 10 GHz emissions from raindrops and from clouds dominate the radiative transfer equation. Because emission and absorption are reciprocal, the combined absorption coefficient of the cloud and the rain can be estimated from the upwelling radiation at these frequencies. After extracting the component due to rain (ka), it may be used to estimate the rainfall rate ξ(R). It is important, therefore, that R depend as strongly as possible on ka. The physical link between R and ka varies depending upon the microwave frequency. The weaker the relation the more sensitive ka and ξ(R) are to variations in the drop-size distribution. In this study it is shown that the scatter in ka and ξ(R), in response to variations in the drop-size distribution, is greatest at 8 and smallest at 3 GHz.

Absolute frequency stabilization of an extended-cavity diode laser against Doppler-free H_2^17O absorption lines at 1384 μm

2009 ◽  
Vol 34 (20) ◽  
pp. 3107 ◽  
Author(s):  
Gianluca Galzerano ◽  
Eugenio Fasci ◽  
Antonio Castrillo ◽  
Nicola Coluccelli ◽  
Livio Gianfrani ◽  
...  
Keyword(s):  
Diode Laser ◽  
Frequency Stabilization ◽  
Absorption Lines ◽  
Absolute Frequency ◽  
Extended Cavity

QED theory of radiation emission and absorption lines for atoms in a strong laser field

2009 ◽  
Vol T135 ◽  
pp. 014022 ◽  
Author(s):  
A Glushkov ◽  
A Loboda ◽  
E Gurnitskaya ◽  
A Svinarenko
Keyword(s):  
Laser Field ◽  
Absorption Lines ◽  
Radiation Emission ◽  
Strong Laser Field ◽  
Strong Laser

STUDIES ON ORIENTED DOMAIN POLYSTYRENE-TGS COMPOSITE FILMS

1995 ◽  
Vol 09 (17) ◽  
pp. 1039-1044
Author(s):  
S.C. MATHUR ◽  
D.S. RAWAT ◽  
H.O. YADAV ◽  
D.C. DUBE ◽  
A.S. BHALLA
Keyword(s):  
Dielectric Constant ◽  
Transition Temperature ◽  
Dielectric Properties ◽  
Domain Structure ◽  
Spontaneous Polarization ◽  
Coercive Field ◽  
Composite Films ◽  
Microwave Frequency ◽  
Ferroelectric Films ◽  
Microwave Frequencies

Polymer ferroelectric films were prepared by dispersing TGS powder in polystyrene. Permittivity versus temperature plots exhibit a peak at around the transition temperature of TGS. The peak gets suppressed with increasing frequency and the trend continues up to microwave frequencies. We observed that the dielectric constant of films at microwave frequency stays close to the dielectric constant of polystyrene. The domain structure of TGS crystals essentially seems to affect their dielectric properties. Single domain films exhibit a higher spontaneous polarization and a higher coercive field.

Sign in / Sign up

Export Citation Format

Share Document