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arXiv · 1604.06514

A coaxial line architecture for integrating and scaling 3D cQED systems

Christopher Axline·Matthew Reagor·Reinier W. Heeres·Philip Reinhold·Chen Wang·Kevin Shain·Wolfgang Pfaff·Yiwen Chu·Luigi Frunzio·Robert J. Schoelkopf
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Abstract

Numerous loss mechanisms can limit coherence and scalability of planar and 3D-based circuit quantum electrodynamics (cQED) devices, particularly due to their packaging. The low loss and natural isolation of 3D enclosures make them good candidates for coherent scaling. We introduce a coaxial transmission line device architecture with coherence similar to traditional 3D cQED systems. Measurements demonstrate well-controlled external and on-chip couplings, a spectrum absent of cross-talk or spurious modes, and excellent resonator and qubit lifetimes. We integrate a resonator-qubit system in this architecture with a seamless 3D cavity, and separately pattern a qubit, readout resonator, Purcell filter and high-Q stripline resonator on a single chip. Device coherence and its ease of integration make this a promising tool for complex experiments.

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Christopher Axline, Matthew Reagor, Reinier W. Heeres, Philip Reinhold, Chen Wang, Kevin Shain, Wolfgang Pfaff, Yiwen Chu, Luigi Frunzio, Robert J. Schoelkopf. 2016-04-22. A coaxial line architecture for integrating and scaling 3D cQED systems. https://doi.org/10.1063/1.4959241

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