Abstract: A method to measure the refractive index of a sample, includes: providing a plasmonic sensor including a sensing surface in contact with the sample; providing an optical resonator, the plasmonic sensor being integrated therein as a reflecting surface; providing a first input field of electromagnetic radiation as a primary carrier; providing a second input field of electromagnetic radiation as a secondary carrier having a second frequency different from the first and defined as: second frequency=first frequency+?v and having a TE and/or a TM polarized component; impinging simultaneously with the first and second input field the plasmonic sensor; tuning the frequency of the first field and/or the value of ?v; detecting a resonator output power corresponding to the first and second intra-cavity fields resonating; determining a difference between the first and the second resonating frequencies; and calculating the refractive index of the sample from the difference.

Abstract: A method to measure the refractive index of a sample, includes: providing a plasmonic sensor including a sensing surface in contact with the sample; providing an optical resonator, the plasmonic sensor being integrated therein as a reflecting surface; providing a first input field of electromagnetic radiation as a primary carrier; providing a second input field of electromagnetic radiation as a secondary carrier having a second frequency different from the first and defined as: second frequency=first frequency+?v and having a TE and/or a TM polarized component; impinging simultaneously with the first and second input field the plasmonic sensor; tuning the frequency of the first field and/or the value of ?v; detecting a resonator output power corresponding to the first and second intra-cavity fields resonating; determining a difference between the first and the second resonating frequencies; and calculating the refractive index of the sample from the difference.

Abstract: A method for measuring an alternating electric field is disclosed. The method includes realizing a first diffraction grating in a first location, in a core of a silica-based optical fiber, and measuring a peak reflection wavelength of the first diffraction grating. The method also includes positioning the optical fiber along a direction having a non-zero component of an electrical field generated by an alternating voltage to be measured, and coupling a substantially monochromatic light to said optical fiber surrounded by the electric field. The method further includes measuring a parameter dependent on a shift of the peak reflection wavelength due to intrinsic mechanical deformation or refractive index change of the material in which the optical fiber and the diffracting grating are realized due to the alternating electric field, and calculating a value of the electric field causing such a measured deformation or refractive index change.

Abstract: A method for measuring an alternating electric field is disclosed. The method includes realizing a first diffraction grating in a first location, in a core of a silica-based optical fiber, and measuring a peak reflection wavelength of the first diffraction grating. The method also includes positioning the optical fiber along a direction having a non-zero component of an electrical field generated by an alternating voltage to be measured, and coupling a substantially monochromatic light to said optical fiber surrounded by the electric field. The method further includes measuring a parameter dependent on a shift of the peak reflection wavelength due to intrinsic mechanical deformation or refractive index change of the material in which the optical fiber and the diffracting grating are realized due to the alternating electric field, and calculating a value of the electric field causing such a measured deformation or refractive index change.

Abstract: The present invention relates to a method and an apparatus to perform frequency comb spectroscopy.

Abstract: The present invention relates to a method and an apparatus to perform frequency comb spectroscopy.

Abstract: An absorption spectroscopy instrument with a light source for providing a beam of light, a modulator to produce a modulated beam of light, a high finesse optical cavity, means for injecting the modulated beam of light off-axis into the high finesse optical cavity and a detector positioned to receive and measure light exiting through said optical cavity. The detector may be a highly sensitive and high bandwidth detector. The modulator may be a one or two-tone modulator having means, such as a plurality of RF synthesizers, for modulating the light source by one or two tones. If one tone of applied modulation is used, the frequency is larger than the absorption bandwidth of the target chemical. In the case where two tones are used, the first frequency is larger than the absorption bandwidth of the target chemical and the second frequency is small relative to the first frequency.

Abstract: An absorption spectroscopy instrument with a light source for providing a beam of light, a modulator to produce a modulated beam of light, a high finesse optical cavity, means for injecting the modulated beam of light off-axis into the high finesse optical cavity and a detector positioned to receive and measure light exiting through said optical cavity. The detector may be a highly sensitive and high bandwidth detector. The modulator may be a one or two-tone modulator having means, such as a plurality of RF synthesizers, for modulating the light source by one or two tones. If one tone of applied modulation is used, the frequency is larger than the absorption bandwidth of the target chemical. In the case where two tones are used, the first frequency is larger than the absorption bandwidth of the target chemical and the second frequency is small relative to the first frequency.