Markus Graefe

Photonic Two-Qubit SWAP Gates

We present a linear photonic approach to implement two-qubit SWAP gates based on engineered arrangements of evanescently coupled waveguides. Our scheme puts forward an alternative to implement two-qubit SWAP gates without using C-Not gates.

Implementation of quantum discrete fractional Fourier transform

In this work we experimentally demonstrate the realization of the discrete fractional Fourier transforms (DFrFT) in both the classical and quantum realm. Our approach is fully integrated and free of bulk optical components.

Arbitrary photonic wave plate operations on-chip: Realizing Hadamard and Pauli-X gates for polarization encoded qubits

We present arbitrary wave plate operations on-chip based on the reorientation of the waveguides optical axis caused by additional stress fields. A successful implementation of Hadamard and Pauli-X gates for quantum light is shown.

Highly Efficient Eigenstate-Assisted Long-Distance Quantum State Transfer in Photonic Lattices

We introduce a new perfect state transfer protocol based on single-photon W-eigenstates of photonic lattices. Such W-eigenstates appear as impulse response of the system, e.g., when single photons are launched into single sites.

Hadamard, Pauli-X, and rotation operation for polarization encoded qubits on chip

We present Hadamard, Pauli-X, and rotation gates of high fidelity for photonic polarization qubits on chip by modifying the orientation of the optical axis and the birefringences strength of femtosecond laser-written waveguides.