The disclosure relates in some aspects to providing miniature power-efficient agile photonic generators of microwave waveforms. Illustrative examples use chip lasers integrated in close thermal proximity with one another to provide a miniature microwave arbitrary waveform generator (AWG). Due to the small size of the lasers and the close integration, common ambient fluctuations from the environment or other sources can be efficiently reduced, yielding improved spectral purity of generated radio-frequency (RF) signals. Tight physical integration also permits a small device footprint with minimal acceleration sensitivity. The lasers may be locked to cavities or other resonators to allow efficient decoupling of the frequency and amplitude modulation of the lasers to provide flexibility to the waveform generator. Exemplary devices described herein can produce frequency chirped signals for radar applications. The frequency chirp may be linear and/or nonlinear. Tuning methods are also described herein.

The disclosure relates in some aspects to providing miniature power-efficient agile photonic generators of microwave waveforms. Illustrative examples use chip lasers integrated in close thermal proximity with one another to provide a miniature microwave arbitrary waveform generator (AWG). Due to the small size of the lasers and the close integration, common ambient fluctuations from the environment or other sources can be efficiently reduced, yielding improved spectral purity of generated radio-frequency (RF) signals. Tight physical integration also permits a small device footprint with minimal acceleration sensitivity. The lasers may be locked to cavities or other resonators to allow efficient decoupling of the frequency and amplitude modulation of the lasers to provide flexibility to the waveform generator. Exemplary devices described herein can produce frequency chirped signals for radar applications. The frequency chirp may be linear and/or nonlinear. Tuning methods are also described herein.

A method for generating a voltage waveform includes providing an optical signal, which comprises one or more sequences of optical pulses, distributing the optical pulses via optical waveguides to a plurality of optical-to-electrical converter units, using the optical-to-electrical converter units to convert the optical pulses into electric driving current pulses, generating voltage pulses by driving Josephson junctions with the electric driving current pulses.

A method for providing an electric waveform at a cryogenic temperatures includes providing an optical signal, which comprises an optical waveform, guiding the optical signal into a cryogenic chamber, and converting the optical waveform of the optical signal into an electric waveform inside the cryogenic chamber.

A method for providing an electric waveform at a cryogenic temperatures includes providing an optical signal, which comprises an optical waveform, guiding the optical signal into a cryogenic chamber, and converting the optical waveform of the optical signal into an electric waveform inside the cryogenic chamber.

According to the present invention, an optical latch circuit includes a voltage detector configured to compare a first power generation voltage input from a first input terminal with a preset first threshold voltage and output a set signal from a determination output terminal when the first power generation voltage exceeds the first threshold voltage, a first photovoltaic element connected between the first input terminal and a grounding point in a forward direction and configured to output a first power generation voltage to the first input terminal according to photovoltaic power when light is radiated, and a feedback resistor inserted between the first input terminal and the determination output terminal.

According to the present invention, an optical latch circuit includes a voltage detector configured to compare a first power generation voltage input from a first input terminal with a preset first threshold voltage and output a set signal from a determination output terminal when the first power generation voltage exceeds the first threshold voltage, a first photovoltaic element connected between the first input terminal and a grounding point in a forward direction and configured to output a first power generation voltage to the first input terminal according to photovoltaic power when light is radiated, and a feedback resistor inserted between the first input terminal and the determination output terminal.

An optoelectronic oscillator for generating an optical and/or electric pulse comb, comprising a monolithically integrated passively mode-coupled semiconductor laser and an optical feedback loop which guides a part of the optical radiation of the semiconductor laser and feeds said part back into the semiconductor laser as feedback pulses. Without the influence of the feedback pulses, the semiconductor laser would emit comb-like optical pulses, hereafter referred to as primary pulses, and in the event of an influence, emits comb-like output pulses which have been influenced by the feedback pulses, said output pulses having a lower temporal jitter or less phase noise than the primary pulses. The feedback loop is damped between 27.5 and 37.5 dB, and the time lag of the feedback loop is selected such that each feedback pulse is incident within the temporal half-value width of each subsequent primary pulse.

An optoelectronic oscillator for generating an optical and/or electric pulse comb, comprising a monolithically integrated passively mode-coupled semiconductor laser and an optical feedback loop which guides a part of the optical radiation of the semiconductor laser and feeds said part back into the semiconductor laser as feedback pulses. Without the influence of the feedback pulses, the semiconductor laser would emit comb-like optical pulses, hereafter referred to as primary pulses, and in the event of an influence, emits comb-like output pulses which have been influenced by the feedback pulses, said output pulses having a lower temporal jitter or less phase noise than the primary pulses. The feedback loop is damped between 27.5 and 37.5 dB, and the time lag of the feedback loop is selected such that each feedback pulse is incident within the temporal half-value width of each subsequent primary pulse.

A capacitor circuit includes a capacitor array including first to n-th capacitors connected to each other in parallel; a select switch circuit including first to n-th select switches connected to the first to n-th capacitors in series, respectively; and a short switch circuit including first to n-th short switches connected to the first to n-th capacitors in parallel, respectively, and operating complementarily to the first to n-th select switches, respectively, wherein n is an integer of 2 or greater.