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Abstract Terahertz (THz) technology has attracted great attention in the past few decades for its unique applications in various fields, including spectroscopy, noninvasive detection, wireless communications, and imaging. In parallel to this, the practical, fast, and broadband modulation of THz waves is becoming indispensable. Two‐dimensional (2D) materials exhibit unusual optical and electrical properties, which has prompted tremendous interest and significant advances in THz modulation. This review provides the recent progress in 2D materials‐based THz modulators, outlining the operating principles, including all‐optical, electro‐optic, magneto‐optic, and other exotic mechanisms. We focus on the recent advances in THz modulation by the designed photonic structures, such as heterostructure, metamaterial, capacitor, optical cavity, and waveguide integration. Lastly, we discussed the challenges and opportunities for 2D materials‐based THz modulators and presented our prospects for the future development.

In this article, a multifunctional and multiscale device which can realize the functions of the magnetic-controlled AND logical operation and detection based on the one-dimensional magnetized InSb photonic structure is proposed and theoretically investigated. Properly modulating the target resonant absorption peak by the external magnetic field, and employing the peak to determine the logical operation, the accurate AND logical operation is fulfilled. Since the target absorption peak holds a superior quality factor value, the designed structure can be considered for detecting the crucial physical quantities, magnetic field, and refractive index. Especially, owing to the magneto-optical effect, time-reversal symmetry and space-reversal symmetry are broken, and the nonreciprocity is generated, which further makes the logical operations and detection of the forward and backward scales can be simultaneously acquired. Numerical analysis gains the optimal sensitivity, the quality value and detection limit. For the detection of magnetic field, and refractive index are 3.13 × 1012 T−1, 9341, 8.4 × 10−5 T, and 1.13 × 1011 RIU−1, 10537, 5.6 × 10−4 RIU, respectively. Surpassing the conventional electromagnetic devices, the designed photonic structure in this work with the combination of magnetic-controlled AND logical operation and detection functions plays a significant constructive role in information communication and photonic computing.

We investigated emission properties of photonic structures with InAs/InGaAlAs/InP quantum dashes grown by molecular beam epitaxy on a distributed Bragg reflector. In high-spatial-resolution photoluminescence experiment, well-resolved sharp spectral lines are observed and single-photon emission is detected in the third telecommunication window characterized by very low multiphoton events probabilities. The photoluminescence spectra measured on simple photonic structures in the form of cylindrical mesas reveal significant intensity enhancement by a factor of 4 when compared to a planar sample. These results are supported by simulations of the electromagnetic field distribution, which show emission extraction efficiencies even above 18% for optimized designs. When combined with relatively simple and undemanding fabrication approach, it makes this kind of structures competitive with the existing solutions in that spectral range and prospective in the context of efficient and practical single-photon sources for fiber-based quantum networks applications.

We report the fabrication and characterization of photonic structures using tapered optical nanofibers. Thanks to the extension of the evanescent electromagnetic field outside of the nanofiber two types of devices can be built: a ring interferometer and a knot resonator. We propose a general approach to predict the properties of these structures using the linear coupling theory. In addition, we describe a new source of birefringence due to the ovalization of a nanofiber under strong bending, known in mechanical engineering as the Brazier effect.