Nanophotonics based on resonant nanostructures and metasurfaces made of halide perovskites have become a prospective direction for efficient light manipulation at the subwavelength scale in advanced photonic designs. One of the main challenges in this field is the lack of large‐scale low‐cost technique for subwavelength perovskite structures fabrication preserving highly efficient luminescence. Here, unique properties of halide perovskites addressed to their extremely low thermal conductivity (lower than that of silica glass) and high defect tolerance to apply projection femtosecond laser lithography for nanofabrication with precise spatial control in all three dimensions preserving the material luminescence efficiency are employed. Namely, with CH3NH3PbI3 perovskite highly ordered nanoholes and nanostripes of width as small as 250 nm, metasurfaces with periods less than 400 nm, and nanowire lasers as thin as 500 nm, corresponding to the state‐of‐the‐art in multistage expensive lithographical methods are created. Remarkable performance of the developed approach allows to demonstrate a number of advanced optical applications, including morphology‐controlled photoluminescence yield, structural coloring, optical‐ information encryption, and lasing.

Donut-shaped laser radiation, carrying orbital angular momentum, namely optical vortex, recently was shown to provide vectorial mass transfer, twisting transiently molten material and producing chiral micro-scale structures on surfaces of different bulk materials upon their resolidification. In this paper, we show for the first time that nanosecond laser vortices can produce chiral nanoneedles (nanojets) of variable size on thin films of such plasmonic materials, as silver and gold films, covering thermally insulating substrates. Main geometric parameters of the produced chiral nanojets, such as height and aspect ratio, were shown to be tunable in a wide range by varying metal film thickness, supporting substrates, and the optical size of the vortex beam. Donut-shaped vortex nanosecond laser pulses, carrying two vortices with opposite handedness, were demonstrated to produce two chiral nanojets twisted in opposite directions. The results provide new important insights into fundamental physics of the vectorial laser-beam assisted mass transfer in metal films and demonstrate the great potential of this technique for fast easy-to-implement fabrication of chiral plasmonic nanostructures.

All-dielectric resonant micro- and nano-structures made of high-index dielectrics have recently emerged as a promising surface-enhanced Raman scattering (SERS) platform which can complement or potentially replace the metal-based counterparts in routine sensing measurements. These unique structures combine the highly-tunable optical response and high field enhancement with the non-invasiveness, i.e. chemically non-perturbing the analyte, simple chemical modification and recyclability. Meanwhile, commercially competitive fabrication technologies for mass production of such structures are still missing. Here, we attest a chemically inert black silicon (b-Si) substrate consisting of randomly-arranged spiky Mie resonators for a true non-invasive (chemically non-perturbing) SERS identification of the molecular fingerprints at low concentrations. Based on the comparative in situ SERS tracking of the para-aminothiophenol (PATP)-to-4,4'-dimercaptoazobenzene (DMAB) catalytic conversion on the bare and metal-coated b-Si, we justify the applicability of the metal-free b-Si for ultra-sensitive non-invasive SERS detection at a concentration level as low as 10-6 M. We performed supporting finite-difference time-domain (FDTD) calculations to reveal the electromagnetic enhancement provided by an isolated spiky Si resonator in the visible spectral range. Additional comparative SERS studies of the PATP-to-DMAB conversion performed with a chemically active bare black copper oxide (b-CuO) substrate as well as SERS detection of the slow daylight-driven PATP-to-DMAB catalytic conversion in the aqueous methanol solution loaded with colloidal silver nanoparticles (Ag NPs) confirm the non-invasive SERS performance of the all-dielectric crystalline b-Si substrate. A proposed SERS substrate can be fabricated using the easy-to-implement scalable technology of plasma etching amenable on substrate areas over 10 × 10 cm2 making such inexpensive all-dielectric substrates promising for routine SERS applications, where the non-invasiveness is of high importance.

Surface-enhanced Raman scattering (SERS) and surface-enhanced photoluminescence (SEPL) are emerging as versatile widespread methods for biological, chemical, and physical characterization in close proximity of nanostructured surfaces of plasmonic materials. Meanwhile, single-step, facile, cheap, and green technologies for large-scale fabrication of efficient SERS or SEPL substrates, routinely demonstrating both broad plasmonic response and high enhancement characteristics, are still missing. In this research, single-pulse spallative micron-size craters in a thick Ag film with their internal nanotexture in the form of nanosized tips are for the first time shown to demonstrate strong polarization-dependent enhancement of SEPL and SERS responses from a nanometer-thick covering Rhodamine 6G layer with average enhancement factors of 40 and 2 × 10(6), respectively. Additionally, the first detailed experimental study is reported for physical processes, underlying the formation mechanisms of ablative nanotextures on such "thick" metal films. Such mechanisms demonstrate a complex "hybrid" fluence-dependent ablation character-appearance of spallative craters, typical for bulk material, at low fluences and formation of upright standing nanotips (frozen nanojets), usually associated with thin-film ablation, in the crater centers at higher fluences. Moreover, special emphasis was made on the possibility to reshape the nanotopography of such spallative craters through multipulse laser-induced merging of their small nanotips into larger ones. The presented approach holds promise to be one of the cheapest and easiest-to-implement ways to mass-fabricate various efficient spallation-nanotextured single-element plasmonic substrates for routine chemo- and biosensing, using MHz-repetition-rate femtosecond fiber laser sources with multiplexed laser-beams.