Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Direct laser writing is shown to dramatically enhance the chemical etch rate of laser crystals yttrium aluminium garnet and sapphire, allowing nanostructuring.
An interferometric homodyne method is employed to measure material-dependent intensity-induced phase shifts of extreme-ultraviolet high harmonics emerging from bulk magnesium oxide and quartz crystals, providing a robust platform for high-harmonic spectroscopy of solids.
A microphotonic astrocomb is demonstrated via temporal dissipative Kerr solitons in photonic-chip-based silicon nitride microresonators with a precision of 25 cm s–1 (radial velocity equivalent), useful for Earth-like planet detection and cosmological research.
A soliton microcomb as an astronomical spectrograph calibrator is presented. It can ultimately have a footprint of a few cubic centimetres, and reduced weight and power consumption, attractive for precision radial velocity measurement.
Coupled lithium niobate ring resonators enable control of a ‘photonic molecule’ by programmed microwave signals. An on-demand optical storage and retrieval system is demonstrated.
Quantum cascade laser frequency combs are coherently locked to an external radio-frequency source even in extremely high-feedback conditions. The internal phase-locking mechanism and the possibility of all-electric stabilization are investigated.
A second harmonic with a conversion efficiency of 0.049% W−1, originating from surface nonlinearity and bulk multipole response in a silica whispering-gallery microcavity, is observed with a continuous-wave pump power below 1 mW.
A quantum walker on a hexagonal glued array of optical waveguides is made inside a glass substrate. The optimal hitting time increases linearly with the layer depth, giving a quadratic speed-up over the hitting performance by classical random walks.
Self-organization far from thermal equilibrium in a thermo-optical feedback process occurring in a random array of Fabry–Pérot resonators is shown, adding new capability to dynamic self-assembly in creating materials with fine-tuned adaptive responses.
A direct wireless-to-optical receiver in a transparent optical link is achieved, thanks to a subwavelength two-dimensionally localized gap-plasmon mixer encoding wireless information directly onto optical signals.
A nonlinear coherent spectroscopy that uses three slightly different repetition-rate frequency combs is demonstrated. A 2D spectrum with comb resolution is generated using only 365 milliseconds of data, almost 600 times faster than previous approaches.
Optical non-reciprocity is experimentally realized with Rb atoms embedded in a ring cavity at room temperature. Random thermal motion of the atoms causes the probe-direction-dependent response assisted by a unidirectional control laser field.
An integrated silicon photonic optical gyroscope achieves two orders of magnitude size reduction and a factor of thirty better phase-shift sensitivity using reciprocal sensitivity enhancement.
By selectively erasing the nonlinear coefficients in a lithium niobate crystal using a femtosecond laser, a 3D nonlinear photonic crystal, with an effective conversion efficiency comparable to that of the typical quasi-phase-matching processes, is demonstrated.
Spin-polarized photon absorption and photoluminescence are reported in reduced-dimensional chiral perovskite materials. The finding indicates that such materials may in the future be useful as a photonic interface for spintronics.
A three-dimensional nonlinear photonic crystal in ferroelectric barium calcium titanate that enables phase matching of nonlinear processes along an arbitrary direction, thereby removing constraints imposed by low-dimensional structures, is experimentally realized.
Nanocrystals assembled into metal–insulator–metal junctions can boost the efficiency of light generation from enhanced inelastic tunnelling to ~2%, which is a two orders of magnitude improvement over previous work, paving the way to on-chip ultrafast and ultracompact light sources.
By seeding a non-resonant aluminium-gallium-arsenide-on-insulator nanowaveguide with 10-GHz picosecond pulses at a low pump power of 85 mW, a single energy-efficient frequency comb source carrying 661 Tbit s–1 of data, equivalent to more than the total Internet traffic today, is achieved.
