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arXiv · 1204.0587

Black-box superconducting circuit quantization

Simon E. Nigg·Hanhee Paik·Brian Vlastakis·Gerhard Kirchmair·Shyam Shankar·Luigi Frunzio·Michel Devoret·Robert Schoelkopf·Steven Girvin
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Abstract

We present a semi-classical method for determining the effective low-energy quantum Hamiltonian of weakly anharmonic superconducting circuits containing mesoscopic Josephson junctions coupled to electromagnetic environments made of an arbitrary combination of distributed and lumped elements. A convenient basis, capturing the multi-mode physics, is given by the quantized eigenmodes of the linearized circuit and is fully determined by a classical linear response function. The method is used to calculate numerically the low-energy spectrum of a 3D-transmon system, and quantitative agreement with measurements is found.

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Simon E. Nigg, Hanhee Paik, Brian Vlastakis, Gerhard Kirchmair, Shyam Shankar, Luigi Frunzio, Michel Devoret, Robert Schoelkopf, Steven Girvin. 2012-04-03. Black-box superconducting circuit quantization. https://doi.org/10.1103/physrevlett.108.240502

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