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A theoretical proposal for time-dependent deflection of X-rays by gravitational and relativistic effects may lead to a table-top technique for probing gravity and relativity.
Nonlinearity engineering is demonstrated by the construction of metamaterial-based photonic crystals. Nonlinear emission and diffraction are controlled and intense focusing is reported.
A discrete-variable quantum key distribution system that is capable of distributing a provably-secure cryptographic key over 307 kilometres is demonstrated at a telecom wavelength.
A pair of 87Sr optical lattice clocks with a statistical agreement of 2 × 10−18 within 6,000 s has been developed. To this end, the behaviour of the blackbody radiation—a major perturbation for optical lattice clocks—was directly investigated.
Lasing is experimentally demonstrated in a direct bandgap GeSn alloy, grown directly onto Si(001). The authors observe a clear lasing threshold as well as linewidth narrowing at low temperatures.