Systems, methods, and techniques for optofluidic analyte detection and analysis using multi-mode interference (MMI) waveguides are disclosed herein. In some embodiments, spatially and spectrally multiplexed optical detection of particles is implemented on an optofluidic platform comprising multiple analyte channels intersecting a single MMI waveguide. In some embodiments, multi-stage photonic structures including a first stage MMI waveguide for demultiplexing optical signals by spatially separating different wavelengths of light from one another may be implemented. In some embodiments, a second stage may use single-mode waveguides and/or MMI waveguides to create multi-spot patterns using the demultiplexed, spatially separated light output from the first stage. In some embodiments, liquid-core MMI (LC-MMI) waveguides that are tunable by replacing a liquid core, heating/cooling the liquid core, and/or deforming the LC-MMI to change its width may be implemented in one or more of the analyte detection/analysis systems disclosed herein.

An integrated mode converter and multiplexer (/demultiplexer) is disclosed, which combines a multimode interference coupler (100), at least one phase-shifter (200) and a symmetrical Y-junction (300). The dispersion of the multimode interference coupler (100) is engineered through subwavelength structures in order to achieve a very wide bandwidth. Several phase-shifter (200) topologies for further bandwidth enhancement are disclosed, as well as architectures for multiplexing a greater number of optical modes.

A device for generating a key has a multimode interferometer which can be coupled to a light source and has a light path having an electro-optical material, the light path being configured to obtain light at an input side, influence the light under the influence of a locally varying refraction index of the electro-optical material and provide influenced light at an output side. The device has a receiver configured to receive the influenced light at the output side, and has an evaluator configured to perform an evaluation based on the influenced light and to generate the key based on the evaluation.

The application discloses an atom interferometer comprising an optical cavity and method of operation thereof. The atom interferometer includes a vacuum chamber, an optical cavity, a source for providing a cloud of atoms in the optical cavity in use, and one or more light sources. The one or more light sources are for generating, in the cavity, in use a first light beam having a first polarisation and at a first frequency for a two-photon interaction in the atoms; and a counterpropagating second light beam having a second polarisation orthogonal to the first polarisation and at a second frequency for the two-photon interaction in the atoms. The atom interferometer also includes an electro-optic element arranged in the cavity to be operable to simultaneously change: the resonant frequency of the cavity for light in the first polarisation to track changes in the frequency of the first light beam to compensate for the doppler shift of the falling atoms in use; and the resonant frequency of the cavity for light in the second polarisation to track changes in frequency of the counterpropagating second light beam to compensate for the doppler shift of the falling atoms in use.

A balanced homodyne detection optical circuit according to the present disclosure is a planar optical waveguide circuit in which a circuit made of an optical waveguide including a dielectric or a semiconductor is formed on a substrate, the balanced homodyne detection optical circuit including an input port of local oscillator light and an input port of measurement light (squeezed light (including excitation light)), wherein a wavelength demultiplexing circuit which demultiplexes only the measurement light is arranged immediately after the input port of measurement light, a 50% multiplexing/demultiplexing circuit is arranged which causes squeezed light having been demultiplexed by the wavelength demultiplexing circuit and the local oscillator light to respectively branch at a branching ratio of 50% and to interfere with each other, and two output ports are arranged to which two outputs from the 50% multiplexing/demultiplexing circuit are guided.

An integrated mode converter and multiplexer (/demultiplexer) combines a multimode interference coupler, at least one phase-shifter and a symmetrical Y-junction. The dispersion of the multimode interference coupler is engineered through subwavelength structures in order to achieve a very wide bandwidth. Several phase-shifter topologies for further bandwidth enhancement are disclosed, as well as architectures for multiplexing a greater number of optical modes.

A high-speed and low-voltage electro-optical modulator based on a lithium niobate-silicon wafer. A silicon wafer is located above a lithium niobate wafer; a lithium niobate-silicon hybrid waveguide is formed by etching a silicon waveguide; and the power of light waves is differently distributed in the lithium niobate-silicon hybrid waveguide by changing the structure of the silicon waveguide. When higher power is distributed in the silicon waveguide, the high-speed and low-voltage electro-optical modulator is suitable for realizing a compact wave splitting function, a wave combining function and a thermo-optical modulation function; and when higher power is distributed in the lithium niobate waveguide, the high-speed and low-voltage electro-optical modulator is suitable for realizing a high-speed and low-voltage electro-optical modulation function. The present invention takes advantage of the lithium niobate and silicon material platforms respectively, and is suitable for high-speed and low-voltage electro-optical modulation.

A light detection and ranging system that may include a light source configured to provide a second optical input signal to a second input port of a multimode interferometer that is phase shifted to a first optical input signal provided to a first input port of the multimode interferometer. The multimode interferometer is configured to provide a second optical output signal to a second optical channel coupled to a second output port of the multimode interferometer, and to provide a first optical output signal to a first optical channel coupled to a first output port of the multimode interferometer. Each of the first optical channel and the second optical channel is configured to emit light to an outside of the light detection and ranging system, and wherein the multimode interferometer is configured to generate a frequency difference between the first optical output signal and the second optical output signal.

The invention provides an optical system and method for outputting a modulated signal comprising a single multimode interference (MMI) device having at least two inputs configured with a fixed phase and an output, wherein the output modulated signal is controlled by modulating the input power of at 5 least one of the inputs. The invention only requires a single MMI device to operate as the relative phase between the two inputs are fixed relative each other and one of the inputs can be used to modulate the output by modulating the power at a single input. In further embodiments, the invention shows how correct phases can be set by a single MMI device. Thus, no more than two 10 MMIs are required in conjunction with phase or amplitude modulating elements to fully generate a BPSK or QPSK signal.

[Object] To provide an optical element and an electronic apparatus having a high response speed and high controllability of a modulation wavelength.

[Solving Means] An optical element according to the present technology includes a first conductor film, a second conductor film, and a dielectric film. The first conductor film has light transmittance and capable of controlling optical transition energy by a Fermi level adjustment. The second conductor film has the light transmittance and capable of controlling the optical transition energy by the Fermi level adjustment. The dielectric film is arranged between the first conductor film and the second conductor film and has the light transmittance and elasticity.