Materials science

Optoelectronics

Physics

Infrared

Lithium niobate

Spectrometer

Computer science

Miniaturization

Optics

Fourier transform spectroscopy

Nanotechnology

Bandwidth (computing)

Wavelength

Broadband

Telecommunications

Nature Photonics

Optical spectrometry is a tool to investigate wavelength-dependent light–matter interactions and is widely used in astronomy, physics and chemistry. Integration and miniaturization of the currently bulky spectrometers will have an impact on applications where compactness and low complexity are key, such as air- and spaceborne missions. A high-resolution spectroscopy principle based on the near-field detection of a spatial standing wave inside a subwavelength waveguide has shown great promise to accomplish some of the aforementioned demands. However, small-scale devices based on this principle face strong bandwidth limitations due to undersampling of the standing wave. Here, we demonstrate an integrated single-waveguide Fourier transform spectrometer with an operational bandwidth of 500 nm in the near- and short-wavelength infrared, not relying on any moving components. The prototype device, with a footprint of less than 10 mm2, exploits the electro-optic properties of thin-film lithium niobate in order to ret...

An integrated broadband spectrometer on thin-film lithium niobate