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The W-Band ($75-110\; \mathrm{GHz}$) sky contains a plethora of informationabout star formation, galaxy evolution and the cosmic microwave background. Wehave designed and fabricated a dual-purpose superconducting circuit tofacilitate the next generation of astronomical observations in this regime byproviding proof-of-concept for both a millimeter-wave low-loss phase shifter,which can operate as an on-chip Fourier transform spectrometer (FTS) and atraveling wave kinetic inductance parametric amplifier (TKIP). Superconductingtransmission lines have a propagation speed that depends on the inductance inthe line which is a combination of geometric inductance and kinetic inductancein the superconductor. The kinetic inductance has a non-linear component with acharacteristic current, $I_*$, and can be modulated by applying a DC current,changing the propagation speed and effective path length. Our test circuit isdesigned to measure the path length difference or phase shift, $\Delta \phi$,between two symmetric transmission lines when one line is biased with a DCcurrent. To provide a measurement of $\Delta\phi$, a key parameter foroptimizing a high gain W-Band TKIP, and modulate signal path length in FTSoperation, our $3.6 \times 2.5\; \mathrm{cm}$ chip employs a pair of $503\;\mathrm{mm}$ long NbTiN inverted microstrip lines coupled to circular waveguideports through radial probes. For a line of width $3\; \mathrm{\mu m}$ and filmthickness $20\; \mathrm{nm}$, we predict $\Delta\phi\approx1767\; \mathrm{rad}$at $90\; \mathrm{GHz}$ when biased at close to $I_*$. We have fabricated aprototype with $200\; \mathrm{nm}$ thick Nb film and the same line length andwidth. The predicted phase shift for our prototype is $\Delta\phi\approx30\;\mathrm{rad}$ at $90\; \mathrm{GHz}$ when biased at close to $I_*$ for Nb.

A Superconducting Phase Shifter and Traveling Wave Kinetic Inductance Parametric Amplifier for W-Band Astronomy