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Quantum dots (QDs) interacting with confined light fields in photonic crystal cavities represent a scalable light source for the generation of single photons and laser radiation in the solid-state platform. The complete control of light-matter interaction in these sources is needed to fully exploit their potential, but it has been challenging due to the small length scales involved. In this work, we experimentally demonstrate the control of the radiative interaction between InAs QDs and one mode of three coupled nanocavities. By non-locally moulding the mode field experienced by the QDs inside one of the cavities, we are able to deterministically tune, and even inhibit, the spontaneous emission into the mode. The presented method will enable the real-time switching of Rabi oscillations, the shaping of the temporal waveform of single photons, and the implementation of unexplored nanolaser modulation schemes.

In this study, we fabricated a photoelectrochemical circuit using GaInAsP photonic crystal nanolasers as a working electrode. Then, we controlled the emission intensity and lasing wavelength of these nanolasers by applying a bias voltage in an ionic solution. The electrochemical working points for the emission intensity and wavelength were observed for the backward and forward biases, respectively. We confirmed that the emission intensity is primarily changed by the surface recombination, which is enhanced by the Schottky barrier near the solid–liquid interface. The wavelength shift is also assumed to be caused by the Pockels effect in the electric double layer of the solution. This control method can maximize and stabilize the performance of photonic biochemical sensors and also become an option in controlling the laser diode characteristics., This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in (Yoshito Saijo et al 2019 App. Phy. Let. 114 221105) and may be found at http://doi.org/10.1063/1.5098119.

We demonstrated for the first time an azimuthally polarized laser source from an electrically driven metallic cavity nanolaser with a physical cavity volume of 0.146 ¿3 (¿¿=¿1416¿nm). Single TE01 mode lasing at 78¿K was achieved by taking the advantages of the large free spectral range in such nanoscale lasers and the azimuthal polarization of lasing emission was verified experimentally. Mode shift controlled by device cavity radius was observed over a large wavelength range from 1.37¿µm to 1.53¿µm. Such metallic cavity nanolaser provides a compact electrically driven laser source for azimuthally polarized beam.

The optical properties of three-layered silver–gold–silica (SGS) nanoshells with gain have been investigated theoretically by using Mie theory. Surface plasmon amplification by stimulated emission of radiation (spaser) phenomena can be observed at two plasmon modes of the active SGS nanoshell in the visible region. It is found with the decrease in the radius of the inner Ag core that the critical value of eg″(ωg) for the super-resonance of the low-energy mode increases first and then decreases while that for the high-energy mode decreases. An interesting overlap between the two curves for the critical value of eg″(ωg) can be found at a special core radius. At this point, two super-resonances can be achieved concurrently at the low- and high-energy modes of the active SGS nanoshell with the same gain coefficient. This dual-frequency spaser based on the bimetallic Ag/Au nanoshell may be an efficient candidate for designing the nanolaser.

Fast and reliable detection of endotoxin (ET) in medical equipment and pharmaceutical products is an essential precursor to clinical treatment. In this study, we demonstrate the use of shifts in wavelength of photonic crystal nanolasers for sensing the Limulus amebocyte lysate reaction, which is a standard method for detecting ET. From working curves of wavelength shift vs ET concentration, whose correlation factors were as high as 98%, we detected a required concentration of 0.001 EU/ml within 33 min and detected a low concentration of 0.0001 EU/ml.

We demonstrate a one-dimensional (1D) photonic crystal (PhC) nanocavity laser composed of hybrid PhC mirrors on a suspended nanobeam (NB) with very small device footprint of 8.5 × 0.57 μm2. The 0th-order mode lasing action with low threshold of 280 μW is observed. Via the optical glue stamping process, the devices are directly transferred onto a flexible polypropylene substrate. Single mode lasing action with effective threshold of 17 μW is achieved. The robust lasing properties of the device with different bending radii R from ∞ to 2.5 mm are obtained. Via finite-element method, we also theoretically address that the lasing wavelength is almost invariant when R > 1.0 mm. This flexible 1D PhC NB laser will be a good candidate for efficient nanolaser in future flexible photonic integrated circuits with ultrahigh component density.

Lasing in a subwavelength metal-clad nanoring resonator has been demonstrated with a tunable emission wavelength, controlled by the width of the ring. The emission wavelength is shown to be tunable within a 10 nm wavelength range by changing the ring width between 240 and 340 nm. This property is expected to mitigate a common nanolaser problem of fine-tuning the emission wavelength without significantly changing the laser dimensions.

Room-temperature visible lasing in CdSe semiconductor nanotube arrays embedded in anodic aluminum oxide template has been demonstrated. The cylindrical nanocavities of anodic aluminum oxide template form laser resonators, and the laser oscillation was achieved through whispering gallery mode gain from the interior semiconductor nanotubes. The linearly polarized stimulated emission, the one dimensionality, and the chemical accessibility to nanotubes render them significant potential for serving as various applications in optoelectronic devices.

A GaInAsP photonic crystal nanolaser was operated by resonant optical pumping in which the effective cavity area was selectively excited. The laser mode intensity was markedly enhanced when the pump wavelength was tuned to a higher-order cavity mode, and room-temperature continuous-wave lasing was obtained in the fundamental mode. Furthermore, the switching behavior due to a modal wavelength shift was clearly observed, suggesting the possibility of bistable operation, and so on.

We recently reported room-temperature continuous-wave operation in a GaInAsP photonic crystal slab nanolaser. In this letter, we demonstrate effective light extraction from the nanolaser monolithically integrated with a passive waveguide by using a GaInAsP butt-joint regrowth technique. Theoretically, the extraction efficiency through the waveguide was calculated to be 80% for the optimum design of the coupling system of the nanolaser and the waveguide. In the experiment, we evaluated a differential quantum efficiency of 4%, which was degraded mainly due to the detection loss of the output light.

Ordered ZnO nanorod arrays with almost uniform rod size have been grown perpendicularly on GaN∕Al2O3 substrates by a controlled vapor phase transport growth method. The ZnO nanorods are [0001] oriented single crystals with diameter of 200nm and length of 4.7μm, with a rod-to-rod spacing of 500nm. Photoluminescence spectra of the rod arrays indicate that the rods are of high crystal quality: very strong, well-separated bound and free exciton emission in the ultraviolet (UV) region are resolved at low temperature. Time resolved microphotoluminescence measurements are performed on single nanorods standing on the substrate which demonstrates lasing behavior with multiple UV lasing modes. Under quasistationary excitation lasing is observed up to room temperature. The lasing emission peaks are sharp, with a linewidth about 0.1nm, and have a fast decay time of ∼8ps. These high crystal quality nanorod arrays may be promising candidates for UV nanolaser devices.

A focused ion beam (FIB) fabricated nanolaser is demonstrated to be able to focus light with power of over 250nW into a 30nm spot. To fabricate a nanolaser, a 100nm thick aluminum film was deposited on the emitting edge of a diode laser. FIB was used to etch various apertures into the film. The power was measured by a scanning near-field optical microscope in the near-field regime with a 10nm separation between the probe and the air bearing surface of the nanolaser. Out of four different shapes under study, “C”-shape aperture was found to have the highest throughput.

Lithium fluoride (LiF) nanowires with diameter of 100 nm-500 nm and length of tens of microns were synthesized via vapor-liquid-solid growth. Cubic-structured single-crystalline LiF nanowires grew along the and crystallographic directions, respectively. The growth of the LiF nanowires was proposed by the catalysis of Zn droplets decomposed from the ZnO. The LiF nanowire could be a potential candidate for the room-temperature tunable color center nanolaser.

A high-density GaN nanowire array has been successfully fabricated through self-organized nanometer-sized holes as mask appearing in InGaN layer. The self-organized nanometer-sized holes are naturally formed during InGaN epitaxial growth using metalorganic chemical vapor deposition technology by modifying growth parameters. Scanning electron microcopy and atomic force microcopy have been used to characterize them. Optical investigation was carried out by room-temperature photoluminescence, which indicated that strong emission from an n-GaN nanowire array was observed at 367 nm, the near-band edge emission wavelength for n-type GaN. The results show that excellent optical properties of the GaN nanowire array can be obtained by this technique. It is important to point out that GaN-based nanolaser or nano-light-emitting diodes with different emission wavelengths can be potentially achieved using this technology.