Quantum interference device, atomic oscillator, and magnetic sensor

Abstract

A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.

1 . A quantum interference device comprising:
 gaseous alkali metal atoms that causes an electromagnetically induced transparency phenomenon by inputting a plurality of resonant light pairs in which center frequencies of each of the plurality of resonant light pairs are different from one another;   a photo-detector that detects the plurality of resonant light pairs passed through the alkali metal atoms and that outputs a detection signal;   a first oscillator that outputs a first oscillation signal, the first oscillation signal in which an oscillation frequency is controlled in accordance with the detection signal;   a second oscillator that outputs a second oscillation signal; and   a resonant light pair generator that generate the plurality of the resonant light pairs by inputting the first and second oscillation signals as a modulation signal.   
     
     
         2 . The quantum interference device according to  claim 1 , wherein
 the resonant light pair generator further comprises:
 a mixer that mixes the first and second oscillation signals and that output a mixed signal; and 
 a light source that outputs light including the plurality of resonant light pairs by inputting the mixed signal as the modulation signal. 
   
     
     
         3 . The quantum interference device according to  claim 1 , wherein
 the resonant light pair generator further comprises:
 a light source that output first light; 
 a mixer that mixes the first and second oscillation signals and that output a mixed signal; and 
 an electro-optic modulation element that outputs second light including the plurality of resonant light pairs by modulating the first light in accordance with the mixed signal. 
   
     
     
         4 . The quantum interference device according to  claim 1 , wherein
 the resonant light pair generator further comprises:
 a light source that output first light; 
 a first electro-optic modulation element that outputs modulated light by modulating the first light in accordance with the first oscillation signal; and 
 a second electro-optic modulation element that outputs second light including the plurality of resonant light pairs by modulating the modulated light in accordance with the second oscillation signal. 
   
     
     
         5 . The quantum interference device according to  claim 1 , wherein
 the resonant light pair generator further comprises:
 a light source that output first light; 
 a first electro-optic modulation element that outputs modulated light by modulating the first light in accordance with the second oscillation signal; and 
 a second electro-optic modulation element that outputs second light including the plurality of resonant light pairs by modulating the modulated light in accordance with the first oscillation signal.