An optical module includes an optical modulator that includes a cutout portion and a first terminal projecting to the inside of the cutout portion, and is configured to perform optical modulation by using an electrical signal input to the first terminal; a driver, at least a part of the driver being housed inside the cutout portion, that is configured to generate an electrical signal; an electrode pattern that extends from the driver inside the cutout portion, and is configured to transmit the electrical signal generated by the driver; and a flexible board having flexibility, one end of the flexible board being electrically connected with the first terminal inside the cutout portion, another end of the flexible board extending in the direction away from the driver, the flexible board being connected with the electrode pattern and configured to input the electrical signal transmitted by the electrode pattern to the first terminal.

The disclosure is directed to devices, systems, and methods for performing quantum state-mediated microwave-to-optical energy conversion. Such quantum state-mediated energy conversion may be achieved via coherent interactions between an optical excitation and microwave electric field mediated by various quantum states in a defect embedded in a crystalline lattice. Such energy conversion enables coherent electro-optical modulation of optical emission from the defect, microwave-optical transduction, optical detection of microwave, and optical frequency mixing in the optical emission from the defect. The optical emission from the defect maintains and carries quantum coherence in the defect. Such devices and methods may be applied in quantum information processing systems.

An optical modulation device includes a substrate including a multilayer portion, an optical waveguide layer on which an optical waveguide is formed in the multilayer portion, and a modulation electrode formed to be divided into a plurality of segments along a propagation direction of the optical waveguide to control a light wave propagating through the optical waveguide, in which in all sections of the electrode or a section excluding a part of the sections, a clearance, measured in an extending direction of the optical waveguide, between gaps between adjacent segments is constant, the multilayer portion includes the optical waveguide layer, a first support layer, and a second support layer, and a refractive index n0 of the optical waveguide layer, a refractive index n1 of the first support layer, and a refractive index n2 of the second support layer have a relationship of n0>n1 and n2>n1.

An optical transmitter includes: an optical modulator; a driver integrated circuit (driver IC) that supplies a modulation electrical signal for the optical modulator; a first wiring board mounted face down by flip-chip mounting to connect the optical modulator and the driver IC; a first Peltier device configured to control a temperature of the optical modulator; and a second Peltier device configured to control a temperature of the driver IC.