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arXiv · 1607.05204

Manipulating Fock states of a harmonic oscillator while preserving its linearity

Kristinn Juliusson·Simon Bernon·Xin Zhou·Vivien Schmitt·Hélène le Sueur·Patrice Bertet·Denis Vion·Mazyar Mirahimi·Pierre Rouchon·Daniel Esteve
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Abstract

We present a new scheme for controlling the quantum state of a harmonic oscillator by coupling it to an anharmonic multilevel system (MLS) with first to second excited state transition frequency on-resonance with the oscillator. In this scheme that we call "ef-resonant", the spurious oscillator Kerr non-linearity inherited from the MLS is very small, while its Fock states can still be selectively addressed via an MLS transition at a frequency that depends on the number of photons. We implement this concept in a circuit-QED setup with a microwave 3D cavity (the oscillator, with frequency 6.4 GHz and quality factor QO=2E-6) embedding a frequency tunable transmon qubit (the MLS). We characterize the system spectroscopically and demonstrate selective addressing of Fock states and a Kerr non-linearity below 350 Hz. At times much longer than the transmon coherence times, a non-linear cavity response with driving power is also observed and explained.

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Kristinn Juliusson, Simon Bernon, Xin Zhou, Vivien Schmitt, Hélène le Sueur, Patrice Bertet, Denis Vion, Mazyar Mirahimi, Pierre Rouchon, Daniel Esteve. 2016-07-18. Manipulating Fock states of a harmonic oscillator while preserving its linearity. https://doi.org/10.1103/physreva.94.063861

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