Quantum teleportation is an important ingredient in distributed quantum networks, and can also serve as an elementary operation in quantum computers. Teleportation was first demonstrated as a transfer of a quantum state of light onto another light beam; later developments used optical relays and demonstrated entanglement swapping for continuous variables. The teleportation of a quantum state between two single material particles (trapped ions) has now also been achieved. Here we demonstrate teleportation between objects of a different nature--light and matter, which respectively represent 'flying' and 'stationary' media. A quantum state encoded in a light pulse is teleported onto a macroscopic object (an atomic ensemble containing 10 caesium atoms). Deterministic teleportation is achieved for sets of coherent states with mean photon number (n) up to a few hundred. The fidelities are 0.58 +/- 0.02 for n = 20 and 0.60 +/- 0.02 for n = 5--higher than any classical state transfer can possibly achieve. Besides being of fundamental interest, teleportation using a macroscopic atomic ensemble is relevant for the practical implementation of a quantum repeater. An important factor for the implementation of quantum networks is the teleportation distance between transmitter and receiver; this is 0.5 metres in the present experiment. As our experiment uses propagating light to achieve the entanglement of light and atoms required for teleportation, the present approach should be scalable to longer distances.

A long-standing goal in the quantum information community has been to realize quantum networks between distant sites. In this tutorial we describe the experimental demonstration of three crucial components in such a network using the off-resonant Faraday interaction between macroscopic atomic ensembles and coherent light. These are the realization of (a) deterministic entanglement between atomic samples in separate environments, (b) quantum mapping of an unknown light state into an atomic memory and (c) disembodied transport of states between quantum nodes via light–atom teleportation.

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Abstract:We report on numerical and experimental characterization of the performance of a fiber link optimized for the delivery of sub-100-fs laser pulses at 1550 nm over several meters of fiber. We investigate the power handling capacity of the link, and demonstrate all-fiber delivery of 1-nJ pulses over a distance of 5.3 m. The fiber link consists of dispersioncompensating fiber (DCF) and standard single-mode fiber. The optical pulses at different positions in the fiber link are measured using frequencyresolved optical gating (FROG). The results are compared with numerical simulations of the pulse propagation based on the generalized nonlinear Schrödinger equation. The high input power capacity of the fiber link allows the splitting and distribution of femtosecond pulses to an array of fibers with applications in multi-channel fiber-coupled terahertz time-domain spectroscopy and imaging systems. We demonstrate THz pulse generation and detection using a distributed fiber link with 32 channels and 2.6 nJ input pulse energy. terahertz time-domain spectrometer operating at 1.5 microm telecom wavelengths," Opt. Express 16(13), 9565-9570 (2008). ©2010 Optical Society of America

We present an effective solution for an all-polarization-maintaining modelocked femtosecond fiber laser operating at the central wavelength of 1028 nm. The laser is based on an Yb-doped active fiber. Modelocking is enabled by a semiconductor saturable absorber mirror, and the central wavelength is enforced by a fiber Bragg grating. The laser is self-starting and demonstrates excellent stability against Q-switching. Pulse energies reach 13 nJ at 34 MHz repetition rate. External compression leads to near transform-limited pulses of 140 fs.

Abstract-We report on a broadband m imaging system based on fiber-coup photoconductive emitters and detectors. 32 emitters are arranged in a planar array. reconstruction algorithms are employed to reco in the imaging plane.