Dual-frequency-comb spectrometer and spectroscopy method for spectroscopic investigation of a sample

A dual-frequency-comb spectrometer, being configured for a spectroscopic investigation of a sample, comprising

• a first frequency comb source device being configured for emitting a first sequence of laser pulses with a first repetition frequency along a first light path,
• a second frequency comb source device being configured for emitting a second sequence of laser pulses with a second repetition frequency along a second light path, wherein the second repetition frequency has a frequency offset relative to the first repetition frequency and the second light path is configured to accommodate the sample to be investigated,
• a first waveguide device being arranged in the first light path for receiving the first sequence of laser pulses and for creating a first frequency comb by supercontinuum generation,
• a second waveguide device being arranged in the second light path for receiving the second sequence of laser pulses and for creating a second frequency comb by supercontinuum generation, wherein the second light path is configured for irradiating the sample with the second frequency comb,
• a detector device being arranged in a third light path where the first and second light paths are combined, for simultaneously sensing the first frequency comb and the second frequency comb after an interaction with the sample, and
• a computing device being arranged for receiving an output of the detector device and being configured for calculating spectroscopic properties of the sample based on the output of the detector device, wherein
• each of the first and second waveguide devices is a multi-core waveguide with a multi-core waveguide section comprising at least two separate single core waveguides having field-coupling via a coupling gap therebetween.