Letters

Patterned chiral liquid crystals operate as configurable optical elements.

An efficient light–matter interface for quantum repeaters is developed. By placing Rb atoms optically confined in a 3D lattice in a ring cavity, an initial retrieval efficiency of 76% together with a 1/e lifetime of 0.22 s are achieved.

Quantum cryptography immune from detector attacks is realized by the development of a source of indistinguishable laser pulses based on optically seeded gain-switched lasers. Key rates exceeding 1 Mb s⁻¹ are demonstrated in the finite-size regime.

Non-equilibrium photoinduced plasmons in a high-mobility graphene monolayer are investigated at infrared wavelengths.

Researchers demonstrate graphene plasmon edge modes at infrared wavelengths. Such modes may offer additional electromagnetic field confinement compared with conventional sheet modes.

Design and fabrication techniques that allow analogous dispersion control in chip-integrated optical microresonators are presented, allowing higher-order, wide-bandwidth dispersion control over an octave of spectrum.

The growth of III–V quantum dot lasers directly onto a silicon substrate aids photonics and electronics integration.

Unconventional interference and statistics of photon fields are studied using two-state ⁸⁷Rb atoms interacting with photons in an optical cavity. The observations are well described by the Tavis-Cummings model in the strong-coupling regime.

The most accurate ratio of the clock transition frequencies between Yb and Sr is measured by using a pair of cryogenic optical lattice clocks. Through common mode rejection of the clock laser noise, a uncertainty of 4.6 × 10⁻¹⁷ is achieved in 150 seconds.

A three-photon entangled state with 3 × 3 × 2 dimensions of its orbital angular momentum is created by using two independent entangled photon pairs from two nonlinear crystals, enabling the development of a new layered quantum communication protocol.

Embedding quantum dots in a perovskite matrix yields efficient light emitters.

Researchers demonstrate correlation of two colours (63.0 and 31.5 nm wavelengths) in a free-electron laser and control photoelectron angular distribution by adjusting phase with 3 attosecond resolution.

A photonic analogue of charge pumping in electronic quantum Hall systems is demonstrated by using a finite 2D square annulus of ring resonators. Topological invariants are investigated by observing the shift of the edge state resonances.

The coherent control of bright excitons in InAs quantum dots is demonstrated by combining heterodyne spectral interferometry with nonlinear multi-wave mixing. The spectro-temporal shape of the coherent emission from InAs quantum dots is manipulated at will.

Scientists demonstrate the temporal analogue of ghost imaging with temporal resolution at the picosecond level. The approach is insensitive to temporal distortion that may occur after the object, and is scalable and can be integrated on-chip.

Single Xe clusters are superheated using an intense optical laser pulse and the structural evolution is imaged with a single X-ray pulse. Ultrafast surface softening on the nanometre scale is resolved within 100 fs at the vacuum/sample interface.

Intrinsic Fano interference in a strongly coupled quantum dot/photonic crystal cavity system is controlled to remove most of the coherently scattered light. This result leads to the first experimental observation of the dynamic Mollow triplet.

Using the attosecond streak camera method, researchers measure the temporal characteristics of coherent, spatially separated attosecond pulses generated from the attosecond lighthouse.

Direct measurement of the electric field of light in the near-infrared is experimentally demonstrated, showing that careful optical filtering allows the time-resolved detection of electric field oscillations with half-cycle durations as short as 2.1 fs, even with a 5 fs sampling pulse.

The refractive index and absorption coefficient of a medium in the infrared range are measured using visible spectral range components. The technique relies on nonlinear interference of infrared and visible photons, produced by down-conversion.