FREQUENCY CONVERSION ELEMENT, FREQUENCY MEASURING UNIT AND FREQUENCY MODULATION AMPLIFIER EMPLOYING IT

摘要

PROBLEM TO BE SOLVED: To obtain a frequency conversion element in which a frequency can be set highly accurately by employing a solid state material for converting the frequency having specified transition angular frequency distribution. SOLUTION: A first transition angular frequencyω13 corresponds to transition between first and third levels and a second transition angular frequencyω23 corresponds to transition between second and third levels. A solid state material having a band transition angular frequency distribution along a lineω23 =a.ω13 +b (a, b are constants and|a|>1) on the plane having two coordinate axes corresponding to these transition angular frequencies is used. When a solid state material having such transition angular frequency distribution is irradiated with coherent lights A, B, population trapping takes place in the region along a lineω23 =ω13 -ωB+ωA. When the light A is irradiated while being controlled by the relative errorδωof angular frequency, relative error of hole position becomesδω/a and a highly accurate frequency can be set when|a|>1.