J. Venkatraman

Experimental implementation of a Raman-assisted six-quanta process

  1. S. O. Mundhada,
  2. A. Grimm,
  3. J. Venkatraman,
  4. Z.K. Minev,
  5. S. Touzard,
  6. N. E. Frattini,
  7. V. V. Sivak,
  8. K. Sliwa,
  9. P. Reinhold,
  10. S. Shankar,
  11. M. Mirrahimi,
  12. and M.H. Devoret
Fault tolerant quantum information processing requires specific nonlinear interactions acting within the Hilbert space of the physical system that implements a logical qubit. The required
order of nonlinearity is often not directly available in the natural interactions of the system. Here, we experimentally demonstrate a route to obtain higher-order nonlinearities by combining more easily available lower-order nonlinear processes, using a generalization of the Raman transitions. In particular, we demonstrate a Raman-assisted transformation of four photons of a high-Q superconducting cavity into two excitations of a superconducting transmon mode and vice versa. The resulting six-quanta process is obtained by cascading two fourth-order nonlinear processes through a virtual state. This process is a key step towards hardware efficient quantum error correction using Schrödinger cat-states.
arxiv pdf