21 research outputs found
Multiphoton Effects Enhanced Due to Ultrafast Photon-Number Fluctuations
Multi-photon processes are the essence of nonlinear optics. Optical harmonics
generation and multi-photon absorption, ionization, polymerization or
spectroscopy are widely used in practical applications. Generally, the rate of
an n-photon effect scales as the n-th order autocorrelation function of the
incident light, which is high for light with strong photon-number fluctuations.
Therefore `noisy' light sources are much more efficient for multi-photon
effects than coherent sources with the same mean power, pulse duration and
repetition rate. Here we generate optical harmonics of order 2-4 from bright
squeezed vacuum (BSV), a state of light consisting of only quantum noise with
no coherent component. We observe up to two orders of magnitude enhancement in
the generation of optical harmonics due to ultrafast photon-number
fluctuations. This feature is especially important for the nonlinear optics of
fragile structures where the use of a `noisy' pump can considerably increase
the effect without overcoming the damage threshold
Multimode ion-photon entanglement over 101 kilometers of optical fiber
A three-qubit quantum network node based on trapped atomic ions is presented.
The ability to establish entanglement between each of the qubits in the node
and a separate photon that has travelled over a 101km-long optical fiber is
demonstrated. By sending those photons through the fiber in close succession, a
remote entanglement rate is achieved that is greater than when using only a
single qubit in the node. Once extended to more qubits, this multimode approach
can be a useful technique to boost entanglement distribution rates in future
long-distance quantum networks of light and matter.Comment: 9 pages, 3 figure
Entanglement of trapped-ion qubits separated by 230 meters
We report on an elementary quantum network of two atomic ions separated by
230 m. The ions are trapped in different buildings and connected with 520(2) m
of optical fiber. At each network node, the electronic state of an ion is
entangled with the polarization state of a single cavity photon; subsequent to
interference of the photons at a beamsplitter, photon detection heralds
entanglement between the two ions. Fidelities of up to are
achieved with respect to a maximally entangled Bell state, with a success
probability of . We analyze the routes to improve these
metrics, paving the way for long-distance networks of entangled quantum
processors
Indistinguishable photons from a trapped-ion quantum network node
Trapped atomic ions embedded in optical cavities are a promising platform to enable long-distance quantum networks and their most far-reaching applications. Here we achieve and analyze photon in-distinguishability in a telecom-converted ion-cavity system. First, two-photon interference of cavity photons at their ion-resonant wavelength is observed and found to reach the limits set by spontaneous emission. Second, this limit is shown to be preserved after a two-step frequency conversion replicating a distributed scenario, in which the cavity photons are converted to the telecom C band and then back to the original wavelength. The achieved interference visibility and photon efficiency would allow for the distribution and practical verification of entanglement between ion-qubit registers separated by several tens of kilometers
Entanglement of trapped-ion qubits separated by 230 meters
We report on an elementary quantum network of two atomic ions separated by 230 m. The ions are trapped in different buildings and connected with 520(2) m of optical fiber. At each network node, the electronic state of an ion is entangled with the polarization state of a single cavity photon; subsequent to interference of the photons at a beamsplitter, photon detection heralds entanglement between the two ions. Fidelities of up to are achieved with respect to a maximally entangled Bell state, with a success probability of . We analyze the routes to improve these metrics, paving the way for long-distance networks of entangled quantum processors
Entanglement of trapped-ion qubits separated by 230 meters
International audienceWe report on an elementary quantum network of two atomic ions separated by 230 m. The ions are trapped in different buildings and connected with 520(2) m of optical fiber. At each network node, the electronic state of an ion is entangled with the polarization state of a single cavity photon; subsequent to interference of the photons at a beamsplitter, photon detection heralds entanglement between the two ions. Fidelities of up to are achieved with respect to a maximally entangled Bell state, with a success probability of . We analyze the routes to improve these metrics, paving the way for long-distance networks of entangled quantum processors
Entanglement of trapped-ion qubits separated by 230 meters
We report on an elementary quantum network of two atomic ions separated by 230 m. The ions are trapped in different buildings and connected with 520(2) m of optical fiber. At each network node, the electronic state of an ion is entangled with the polarization state of a single cavity photon; subsequent to interference of the photons at a beamsplitter, photon detection heralds entanglement between the two ions. Fidelities of up to are achieved with respect to a maximally entangled Bell state, with a success probability of . We analyze the routes to improve these metrics, paving the way for long-distance networks of entangled quantum processors