Vertical Emitting Nanowire Vector Beam Lasers

Abstract

Due to the peculiar structured light field with spatially variant polarizations on the same wavefront, vector beams (VBs) have sparked research enthusiasm in developing advanced super-resolution imaging and optical communications techniques. A compact VB nanolaser is intriguing for VB applications in miniaturized photonic integrated circuits. However, determined by the diffraction limit of light, it is a challenge to realize a VB nanolaser in the subwavelength scale because the VB lasing modes should have laterally structured distributions. Here, we demonstrate a VB nanolaser made from a 300 nm thick InGaAs/GaAs nanowire (NW). To select the high-order VB lasing mode, a standing NW as-grown from the selective-area-epitaxial (SAE) growth process is utilized, which has a bottom donut-shaped interface with the silicon oxide growth substrate. With this donut-shaped interface as one of the reflective mirrors of the nanolaser cavity, the VB lasing mode has the lowest threshold. Experimentally, a single-mode VB lasing mode with a donut-shaped amplitude and azimuthally cylindrical polarization distribution is obtained. Together with the high yield and uniformity of the SAE-grown NWs, our work provides a straightforward and scalable path toward cost-effective co-integration of VB nanolasers on potential photonic integrated circuits.

Vector Beam Generation from Standing Hollow GaN Nanowire Lasers on Sapphire Substrates

“…When the polarizer is rotated, polarized light along the angle of the polarizer can be extracted. Such a pattern is a characteristic of a typical vector beam. , The FFP was further confirmed in FEM simulations (Supporting Information 5).…”

“…Small lasers with hollow structures have been demonstrated in the form of micrometer-sized rolled-up semiconductor emitters and lasers. , However, they are much larger than semiconductor nanowires and are still too big to be integrated into optical circuits as nanodevices. Recently, vector beams have been generated from nanowires with a donut-shaped reflector at the bottom under cryogenic temperature. , In particular, it has been shown that nanowires support multimode propagation, and the vector beam is generated from a higher-order mode. Generally, however, the fundamental mode has a higher effective refractive index and is advantageous for laser oscillation because more light is confined in the nanowire.…”

“…Recently, vector beams have been generated from nanowires with a donut-shaped reflector at the bottom under cryogenic temperature. 34,35 In particular, it has been shown that nanowires support multimode propagation, and the vector beam is generated from a higher-order mode. Generally, however, the fundamental mode has a higher effective refractive index and is advantageous for laser oscillation because more light is confined in the nanowire.…”

Axial Growth Characteristics of Optically Active InGaAs Nanowire Heterostructures for Integrated Nanophotonic Devices

“…14,15 Additionally, the small diameter and lateral relaxation of strain within the NW enable the formation of axial heterostructures well beyond the critical thickness limit of planar structures. 16 Such platform can, thus, realize various 1D heterostructure devices, such as resonant tunneling diodes, 17,18 ultrafast photodetectors 19,20 and lasers, 21,22 terahertz NW quantum cascade lasers, 23 and singlephoton sources based on NW quantum dots (NW-QDs). 24−30 Particularly, the deterministic nature of single, site-controlled quantum disks or QDs embedded along the NW growth axis offers attractive capabilities beyond those of conventional Stranski−Krastanov growth.…”

“…Free-standing III–V semiconductor nanowires (NWs) have evolved into a promising material platform with various potential device applications in electronics, optoelectronics, and integrated photonics. − Their tiny footprint enables compatibility with lattice-mismatched substrates, such as silicon (Si), , and the unique one-dimensional (1D) optical cavity structure with a large refractive index contrast facilitates effective confinement and low-loss propagation of optical modes along the NW’s axial direction. , Additionally, the small diameter and lateral relaxation of strain within the NW enable the formation of axial heterostructures well beyond the critical thickness limit of planar structures . Such platform can, thus, realize various 1D heterostructure devices, such as resonant tunneling diodes, , ultrafast photodetectors , and lasers, , terahertz NW quantum cascade lasers, and single-photon sources based on NW quantum dots (NW-QDs). − Particularly, the deterministic nature of single, site-controlled quantum disks or QDs embedded along the NW growth axis offers attractive capabilities beyond those of conventional Stranski–Krastanov growth. Such NW-QDs or -disks have demonstrated great potential as quantum light sources and low-threshold lasers with high material gain due to their intriguing physical properties, including enhanced light–matter interaction and efficient carrier confinement. ,,− It has also been demonstrated that NW-QDs grown along the [111] orientation have a vanishing fine-structure splitting due to their symmetry, which can be ideal candidates for generating entangled photon pairs. , Thus, the realization of high-quality axial heterostructures within III–V NWs, featuring abrupt interfaces and controlled composition, is a crucial step to harnessing the full potential of these nanomaterials for practical applications.…”