Interfaces for quantum state transfer

Pei Pei, Huang He-Fei, Yanqing Guo +2 more

We propose a scheme to implement quantum state transfer between two distant quantum nodes via a hybrid solid–optomechanical interface. The quantum state is encoded on the native superconducting qubit, and transferred to the microwave photon, then the optical photon successively, which afterwards is transmitted to the remote node by cavity leaking, and finally the quantum state is transferred to the remote superconducting qubit. The high efficiency of the state transfer is achieved by controllable Gaussian pulses sequence and numerically demonstrated with theoretically feasible parameters. Our scheme has the potential to implement unified quantum computing–communication–computing, and high fidelity of the microwave–optics–microwave transfer process of the quantum state.

Lorena Ballesteros Ferraz

Hanzhe Xi, Pei Pei

We propose a protocol to realize fast high-fidelity quantum state transfer between distant optomechanical interfaces connected by a continuum waveguide. The scheme consists of three steps: two accelerating adiabatic processes joined by a population conversion process. In comparison to the traditional adiabatic technique, our method reaches a higher transfer fidelity with a shorter time. Numerical results show that the fidelity of this transfer scheme in the dissipative system mainly depends on the protocol speed and the coupling strength of the waveguide and cavities. Assisted by inverting the pulse sequence, bidirectional transfer can be implemented, indicating the potential to build a quantum network.

M. Bertolotti, Fabio Antonio Bovino, Concita Sibilia

Radim Filip

We propose a continuous-variable quantum interface that transfers an arbitrary unknown quantum state between a well-controllable source oscillator and a weakly controllable noisy target oscillator through an arbitrary Gaussian coupling. The unit fidelity of transfer is achieved by the preprocessing of the source state involving an ancillary system, collective measurement of the source after the coupling together with the ancilla, and by a subsequent feed-forward correction of the target. Particularly, these techniques allow the transfer of quantum states of light to arbitrarily noisy matter systems.

Georgios M. Nikolopoulos, Igor Jex