Abstract: According to an example aspect of the present invention, there is provided a travelling wave parametric amplifier comprising a waveguide transmission line comprising therein at least ten Josephson elements, wherein each of the at least ten Josephson element comprises a loop, with exactly one Josephson junction of first size on one half of the loop and at least two Josephson junctions of a second size on a second half of the loop, the second size being larger than the first size, a flux bias line configured to generate a magnetic flux threading each of the at least one loop, and a set of resistors coupled with the flux bias line.

Abstract: A detector of microwave radiation includes a signal input and a detector output. An absorber element of ohmic conductivity is coupled to said signal input through a first length of superconductor. A variable impedance element, the impedance of which is configured to change as a function of temperature, is coupled to the detector output through a second length of superconductor. The detector also includes a heating input and a heating element coupled to the heating input through a third length of superconductor. The absorber element, the variable impedance element, and the heating element are coupled to each other through superconductor sections of lengths shorter than any of said first, second, and third lengths of superconductor.

Abstract: According to an example aspect of the present invention, there is provided a travelling wave parametric amplifier comprising a waveguide transmission line comprising therein at least ten Josephson elements, wherein each of the at least ten Josephson element comprises a loop, with exactly one Josephson junction of first size on one half of the loop and at least two Josephson junctions of a second size on a second half of the loop, the second size being larger than the first size, a flux bias line configured to generate a magnetic flux threading each of the at least one loop, and a set of resistors coupled with the flux bias line.

Abstract: A solution for reading detector arrays is disclosed. The solution comprises generating (400) an excitation signal, varying (402) the frequency of the excitation signal in time, supplying (404) the excitation signal to a detector array comprising a set of thermal detectors. The number of detectors corresponds to the frequencies of the excitation signal. In the solution, the signal is demodulated (406) at the output of the detector array and time-multiplexed base band signal is obtained. An analogue to digital conversion is performed (408) to the time-multiplexed base band signal and the base band signal is demultiplexed (410) to obtain a set of detector signals.

Abstract: A detector of microwave radiation comprises a signal input and a detector output. An absorber element of ohmic conductivity is coupled to said signal input through a first length of superconductor. A variable impedance element, the impedance of which is configured to change as a function of temperature, is coupled to the detector output through a second length of superconductor. There is also a heating input and a heating element coupled to the heating input through a third length of superconductor. The absorber element, the variable impedance element, and the heating element are coupled to each other through superconductor sections of lengths shorter than any of said first, second, and third lengths of superconductor.

Abstract: A solution for reading detector arrays is disclosed. The solution comprises generating (400) an excitation signal, varying (402) the frequency of the excitation signal in time, supplying (404) the excitation signal to a detector array comprising a set of thermal detectors. The number of detectors corresponds to the frequencies of the excitation signal. In the solution, the signal is demodulated (406) at the output of the detector array and time-multiplexed base band signal is obtained. An analogue to digital conversion is performed (408) to the time-multiplexed base band signal and the base band signal is demultiplexed (410) to obtain a set of detector signals.