Ivette Fuentes

Motion and gravity effects in the precision of quantum clocks

  1. Joel Lindkvist,
  2. Carlos Sabín,
  3. Göran Johansson,
  4. and Ivette Fuentes
We show that motion and gravity affect the precision of quantum clocks. We consider a localised quantum field as a fundamental model of a quantum clock moving in spacetime and show
that its state is modified due to changes in acceleration. By computing the quantum Fisher information we determine how relativistic motion modifies the ultimate bound in the precision of the measurement of time. While in the absence of motion the squeezed vacuum is the ideal state for time estimation, we find that it is highly sensitive to the motion-induced degradation of the quantum Fisher information. We show that coherent states are generally more resilient to this degradation and that in the case of very low initial number of photons, the optimal precision can be even increased by motion. These results can be tested with current technology by using superconducting resonators with tunable boundary conditions.
arxiv pdf

Towards universal quantum computation through relativistic motion

  1. David Edward Bruschi,
  2. Carlos Sabín,
  3. Pieter Kok,
  4. Göran Johansson,
  5. Per Delsing,
  6. and Ivette Fuentes
We show how to use relativistic motion to generate continuous variable Gaussian cluster states within cavity modes. Our results can be demonstrated experimentally using superconducting
circuits where tunable boundary conditions correspond to mirrors moving with velocities close to the speed of light. In particular, we propose the generation of a quadripartite square cluster state as a first example that can be readily implemented in the laboratory. Since cluster states are universal resources for universal one-way quantum computation, our results pave the way for relativistic quantum computation schemes.
arxiv pdf

Relativistic Quantum Teleportation with superconducting circuits

  1. Nicolai Friis,
  2. Antony R. Lee,
  3. Kevin Truong,
  4. Carlos Sabín,
  5. Enrique Solano,
  6. Göran Johansson,
  7. and Ivette Fuentes
We study the effects of relativistic motion on quantum teleportation and propose a realizable experiment where our results can be tested. We compute bounds on the optimal fidelity of
teleportation when one of the observers undergoes non-uniform motion for a finite time. The upper bound to the optimal fidelity is degraded due to the observer’s motion however, we discuss how this degradation can be corrected. These effects are observable for experimental parameters that are within reach of cutting-edge superconducting technology.
arxiv pdf