Related papers: Photon echo with a few photons in two-level atoms
Decoy states have been proven to be a very useful method for significantly enhancing the performance of quantum key distribution systems with practical light sources. While active modulation of the intensity of the laser pulses is an…
We present experimental results on a method to perform polarimetry on ensembles of single photons. Our setup is based on a measurement method known to be optimal for estimating the state of two level systems. The setup has no moving parts…
The future of long-distance quantum communication relies on the availability of quantum memory, i.e. devices that allow temporal storage of quantum information. We review research related to quantum state storage based on a photon-echo…
Physical systems with discrete energy levels are ubiquitous in nature and are fundamental building blocks of quantum technology. Realizing controllable artifcial atom- and molecule-like systems for light would allow for coherent and dynamic…
Coherent generation of indistinguishable single photons is crucial for many quantum communication and processing protocols. Solid-state realizations of two-level atomic transitions or three-level spin-$\Lambda$ systems offer significant…
A quantum memory protocol of controlled ac Stark echoes (CASE) based on a double rephasing photon echo scheme via controlled Rabi flopping is proposed. A double rephasing scheme of photon echoes inherently satisfies the no-population…
Integrated single-photon detectors open new possibilities for monitoring inside quantum photonic circuits. We present a concept for the in-line measurement of spatially-encoded multi-photon quantum states, while keeping the transmitted ones…
Within optical quantum information processing, single-photon sources based on a two-level system in a semiconductor material allow for on-demand generation of single photons. To initiate the spontaneous emission process, it is necessary to…
Long-lived storage of single photons is a fundamental requirement for enabling quantum communication and foundational tests of quantum physics over extended distances. While the implementation of a global-scale quantum network requires…
We present a quantum memory protocol that allows to store light in ensembles of two-level atoms, e.g. rare-earth ions doped into a crystal, by modulating the refractive index of the host medium of the atoms linearly in time. We show that…
The CLARO-CMOS is an application specific integrated circuit (ASIC) designed for fast photon counting with pixellated photodetectors such as multi-anode photomultiplier tubes (Ma-PMT), micro-channel plates (MCP), and silicon…
The final goal of quantum hypothesis testing is to achieve quantum advantage over all possible classical strategies. In the protocol of quantum reading this advantage is achieved for information retrieval from an optical memory, whose…
We demonstrate experimentally the storage and retrieval of weak coherent light fields at telecommunication wavelengths in a solid. Light pulses at the single photon level are stored for a time up to 600 ns in an Erbium-doped Y$_2$SiO$_5$…
Imaging systems' performance at low light intensity is affected by shot noise, which becomes increasingly strong as the power of the light source decreases. In this paper we experimentally demonstrate the use of deep neural networks to…
For near-term quantum devices, an important challenge is to develop efficient methods to certify that noise levels are low enough to allow potentially useful applications to be carried out. We present such a method tailored to photonic…
Conditional addition of photons represents a crucial tool for optical quantum state engineering and it forms a fundamental building block of advanced quantum photonic devices. Here we report on experimental implementation of the conditional…
We present an efficient photon-echo experiment based on atomic frequency combs [Phys. Rev. A 79, 052329 (2009)]. Echoes containing an energy of up to 35% of that of the input pulse are observed in a Pr3+-doped Y2SiO5 crystal. This material…
It has recently been discovered that the optical analogue of a gradient echo in an optically thick material could form the basis of a optical memory that is both completely efficient and noise free. Here we present analytical calculation…
Photons are the ideal carriers of quantum information for communication. Each photon can have a single qubit or even multiple qubits encoded in its internal quantum state, as defined by optical degrees of freedom such as polarization,…
We propose boson sampling from a system of coupled photons and Bose-Einstein condensed atoms placed inside a multi-mode cavity as a simulation process testing quantum advantage of quantum systems over classical computers. Consider a…