Experimental Implementation of a Raman-Assisted Eight-Wave Mixing Process
S.O. Mundhada, A. Grimm, Jayameenakshi Venkatraman, Zlatko Minev, Steven Touzard, N.E. Frattini, Volodymyr Sivak, K. Sliwa, P. Reinhold, S. Shankar, Mazyar Mirrahimi, M.H. Devoret · Physical Review Applied · 2019
Engineering higher-order nonlinear interactions is vital in autonomous protection of quantum systems against errors. Such interactions are often not directly available, though, or are slow compared to error rates of the system. The authors present a nonlinear eight-wave mixing process that exchanges four photons of a harmonic oscillator with two excitations of a transmon-qubit mode and two pump photons, by combining more accessible lower-order interactions via a sort of Raman transition. Surprisingly, this technique produces a stronger interaction than a six-wave mixing process in the same system. This eight-wave mixing process is expected to become a key component of autonomous continuous-variable quantum error correction.