G. Puebla-Hellmann

Realization of Deterministic Quantum Teleportation with Solid State Qubits

  1. L. Steffen,
  2. A. Fedorov,
  3. M. Oppliger,
  4. Y. Salathe,
  5. P. Kurpiers,
  6. M. Baur,
  7. G. Puebla-Hellmann,
  8. C. Eichler,
  9. and A. Wallraff
Transferring the state of an information carrier from a sender to a receiver is an essential primitive in both classical and quantum communication and information processing. In a quantum
process known as teleportation the unknown state of a quantum bit can be relayed to a distant party using shared entanglement and classical information. Here we present experiments in a solid-state system based on superconducting quantum circuits demonstrating the teleportation of the state of a qubit at the macroscopic scale. In our experiments teleportation is realized deterministically with high efficiency and achieves a high rate of transferred qubit states. This constitutes a significant step towards the realization of repeaters for quantum communication at microwave frequencies and broadens the tool set for quantum information processing with superconducting circuits.
arxiv pdf

Realization of GHz-frequency impedance matching circuits for nano-scale devices

  1. G. Puebla-Hellmann,
  2. and A. Wallraff
Integrating nano-scale objects, such as single molecules or carbon nanotubes, into impedance transformers and performing radio-frequency measurements allows for high time-resolution
transport measurements with improved signal-to-noise ratios. The realization of such transformers implemented with superconducting transmission lines for the 2-10 GHz frequency range is presented here. Controlled electromigration of an integrated gold break junction is used to characterize a 6 GHz impedance matching device. The real part of the RF impedance of the break junction extracted from microwave reflectometry at a maximum bandwidth of 45 MHz of the matching circuit is in good agreement with the measured direct current resistance.
arxiv pdf