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Travelling wave parametric amplifiers (TWPAs) made from highly nonlinear reactive superconducting thin films have been demonstrated to be a viable technology for various quantum applications, including fundamental physics experiments such as astronomy and axion dark matter searches, as well as commercial applications like quantum computational and communication systems. In this paper, we present the design of a kinetic inductance TWPA comprising a patterned titanium nitride film that can operate at 0.3K to demonstrate the feasibility of operation closer to 1K temperature, paving the way to achieve even higher bath temperature operation. We discuss in detail the design of our TWPA, along with the predicted gain-bandwidth product and other characteristics. We perform the preliminary experimental investigation of the thin film properties and compare that with the simulated results. We found that there are several discrepancies between the measured and the predicted behaviour of the thin film. We attribute these differences to the fact that the fabricated thin film has a different gap voltage, resistivity and thickness to what we expected. With a new set of estimated parameters, we successfully reproduce the measured transmission profile. We further show that by utilising bridges to ensure equipotential grounds for the CPW lines, we are able to reduce the rippling effect and achieve a higher gain with broader bandwidth. We expect that our TWPA can achieve higher than 20 dB gain from approximately 0–8 GHz.

An advanced seismic compression technique is proposed to manage seismic data in a world of ever increasing data volumes in order to maintain productivity without compromising interpretation results. A separable 3-D discrete wavelet transform (DWT) using long biorthogonal filters is used. The computation efficiency of the DWT is improved by factoring the wavelet filters using the lifting scheme. In addition, the lifting scheme offers: 1) a dramatic reduction of the required auxiliary memory, 2) an efficient combination with parallel rendering algorithms to perform arbitrary surface and volume rendering for interactive visualization, and 3) an easy integration in the parallel I/O seismic data loading routines. The proposed technique is tested on a seismic volume from the Stratton field in South Texas. The resulting 3-level multiresolution decomposition yields 21 detail sub-volumes and a unique low-resolution sub-volume. The detail wavelet coefficients are quantized with an adaptive threshold uniform scalar quantizer (TUSQ). The scale-dependent thresholds are determined with the Stein unbiased risk estimate (SURE) principle. As the approximation coefficients represent a smooth low-resolution version of the input data they are only quantized using a uniform scalar quantizer (USQ). Finally a runlength plus a Huffman encoding are applied for binary coding of the quantized coefficients.