Volume 17 Issue 4, April 2023

Nature Photonics talks to Mark Hahnel, the founder and CEO of Figshare, a popular data repository, about the benefits and trends in making data open and shareable.

The Ti:Sa laser, a workhorse of any optics laboratory, is typically a bench-top system. A hybrid integration approach now enables a low-threshold photonic-circuit-integrated Ti:Sa laser the size of a fingernail.

A photothermal microscopy technique overcomes the diffraction limit by exploiting the spatiotemporal dynamics of heat dissipation within the imaging volume, offering new opportunities for super-resolution, bond-selective and label-free imaging of biological targets.

Due to dispersion, the group velocity of laser pulses propagating in plasmas slows down with increasing wavelength, which presents challenges for precision-controlled plasma interactions. Now, new techniques for spatio-temporal pulse shaping have lifted this limitation in the demonstration of short-pulse table-top soft X-ray lasers.

The combination of optical phase conjugation and light amplification enables wavefront shaping with simultaneously optimized operational speed, number of control degrees of freedom and energy of the focused wavefront. Shaping with a 10 μs latency time over about 10⁶ control modes and energy gain approaching unity is demonstrated.

Current LiDAR approaches suffer from congestion issues, which affect measurement performance and increased system complexity. Now researchers demonstrate a chaotic microcomb that exhibits congestion-immune naturally orthogonalized light channels.

Centimetre-sized formamidinium-caesium lead bromide (FACsPbBr₃) single crystals were grown at high yield from low-purity precursors. High (84%) charge collection efficiency and energy resolution (2.9% for 662 keV ¹³⁷Cs) for γ-rays were demonstrated.

A continuous string of indistinguishable photons entangled in a cluster state is generated on demand from an InAs/GaAs quantum dot. The confined heavy-hole spin is used as an entangler. Under an externally tuned magnetic field, an optimized characteristic entanglement decay length of about ten photons is obtained.

Photothermal relaxation localization microscopy allows super-resolution imaging of non-fluorescent targets by leveraging spatial-dependent heat dissipation in photothermal microscopy. Individual lipid droplets and their distribution in living cells are imaged at spatial resolutions down to 120 nm.

A prototype integrated Ti:Sa laser is demonstrated by bonding the Ti:Sa gain medium on silicon nitride microring resonators. Lasing is demonstrated between 730 nm and 830 nm with a threshold power as low as 6.5 mW.

Researchers use zinc-doped CuInSe₂ nanocrystals as an alternative to lead chalcogenides for near-infrared upconversion. Upconversion to yellow with an external quantum efficiency reaching 16.7% is achieved, which can also be merged with photoredox catalysis for rapid solar synthesis.

Researchers use pulse front curvature and temporal chirp to control the group velocity of a soft X-ray laser pump beam, resulting in improved energy extraction and reduced pulse duration.

We demonstrate plasmonic micro-racetrack modulators for intensity-modulated transmission at 408 Gbps and 12.3 femtojoules per bit. The modulators offer wide bandwidth and the devices show improved temperature stability over conventional approaches.

Researchers demonstrate that the dark saturation current in organic photodiodes is fundamentally limited by mid-gap trap states. This leads to an upper limit for specific detectivity.