We present the first quantum key distribution (QKD) experiment over multicore fiber. With space division multiplexing, we demonstrate that weak QKD signals can coexist with classical data launched at full power in a 53 km 7-core fiber, while showing negligible degradation performance. Based on characterization of intercore crosstalk, perform additional simulations highlighting bandwidths beyond 1Tb/s be supported high speed same

Abstract Optoelectronic terahertz modulators, operated by actively tuning metamaterial, plasmonic resonator structures, have helped to unlock a myriad of applications, ranging from spectroscopy and imaging communications. At the same time, due inherently versatile dispersion properties metamaterials, they offer unique platforms for studying intriguing phenomena such as negative refractive index slow light. Active resonance frequency metamaterial working in regime is achieved integrating...

The terahertz (THz) region of the electromagnetic spectrum holds great potential in many fields study, from spectroscopy to biomedical imaging, remote gas sensing, and high speed communication. To fully exploit this potential, fast optoelectronic devices such as amplitude phase modulators must be developed. In work, we present a room temperature external THz modulator based on plasmonic bow-tie antenna arrays with graphene. By applying modulating bias back gate electrode, conductivity...

Abstract Terahertz (0.1–10 THz corresponding to vacuum wavelengths between 30 μm and 3 mm) research has experienced impressive progress in the last few decades. The importance of this frequency range stems from unique applications several fields, including spectroscopy, communications, imaging. emitters have great development recently with advent quantum cascade laser, improvement covered by electronic-based sources, increased performance versatility time domain spectroscopic systems based...

Abstract Active control of chirality in artificial media such as metamaterials is fundamental many scientific areas, ranging from research into optical phenomena to the investigation novel materials, spectroscopy, and imaging. Precise light polarization states has great importance for light‐matter interaction chemistry biology, with diverse chiral properties react differently incoming light. In this work an active double layer metamaterial device based on vertically stacked ring resonators...

Optoelectronic modulators that operate by the electrical tuning of plasmonic resonator structures have demonstrated fast (>MHz) manipulation terahertz (THz) radiation for communications, imaging, and spectroscopy applications. Among this class THz device, chiral metamaterial-based polarization attracted increasing attention due to importance control chemistry, biology, applications, as well communication protocols. In paper, active modulation a quantum cascade laser is 2D metamaterial array....

We present a terahertz (THz) scattering near-field optical microscope (s-SNOM) based on quantum cascade laser implemented as both source and detector in self-mixing scheme utilizing resonant quartz tuning forks sensitive nanopositioning element. The homemade s-SNOM, fork metallic tip, operates tapping mode with spatial resolution of ∼78 nm. is realized from bound-to-continuum active region design central emission ∼2.85 THz, which has been lens-coupled order to maximize the feedback into...

We present a fast room-temperature terahertz detector based on interdigitated bow-tie antennas contacting graphene. Highly efficient photodetection was achieved by using two metals with different work functions as the arms of antenna Arrays bow-ties were fabricated in order to enhance responsivity and coupling incoming light detector, realizing an imaging system. The device has been characterized tested quantum cascade laser emitting single frequency around 2 THz, yielding ∼34 μA/W...

Many mid- and far-infrared semiconductor photodetectors rely on a photonic response, when the photon energy is large enough to excite extract electrons due optical transitions. Toward terahertz range with energies of few milli–electron volts, classical mechanisms are used instead. This case in two-dimensional electron systems, where detection dominated by plasmonic mixing scattering-based thermal phenomena. Here, we report observation quantum, collision-free phenomenon that yields giant...

We report the fast amplitude modulation of a quantum cascade laser emitting in single-mode operation terahertz frequency range by employing compact, integrated devices based on interplay between plasmonic antenna arrays and monolayer graphene. By acting carrier concentration graphene, optical response these resonances was modified. The modulator's characteristics have been studied using both time domain spectroscopic systems, yielding broad resonant arrays, lasers, providing us with narrow...

Metamaterial photonic integrated circuits with arrays of hybrid graphene-superconductor coupled split-ring resonators (SRR) capable modulating and slowing down terahertz (THz) light are introduced proposed. The device's optical responses, such as electromagnetic-induced transparency (EIT) group delay, can be modulated in several ways. First, it is electrically by changing the conductivity carrier concentrations graphene. Alternatively, response modified acting on device temperature...

Active control of the amplitude and frequency terahertz sources is an essential prerequisite for exploiting a myriad applications in imaging, spectroscopy, communications. Here we present optoelectronic, external modulation technique applied to quantum cascade laser which holds promise addressing number important challenges this research area. A hybrid metamaterial/graphene device implemented into cavity set-up allowing optoelectronic tuning feedback laser. We demonstrate powerful,...

RD, HEB and DAR acknowledge financial support from the Engineering Physical Sciences Research Council (Grant No. EP/J017671/1, Coherent Terahertz Systems). SH acknowledges funding EPSRC EP/K016636/1, GRAPHTED). KN University of Cambridge Nanoscience Doctoral Training Centre (EPSRC EP/G037221/1) for support.

We demonstrate the amplitude stabilization of a 2.85 THz quantum cascade laser with graphene loaded split-ring-resonator array acting as an external modulator. The transmittance modulator can be actively changed by modifying conductivity via electrostatic back-gating. operates at room temperature and is capable modulating power level thus stabilizing output proportional-integral-derivative feedback control loop. stability was enhanced more than 10 times through tuning modulation....

Photonic engineering of the terahertz emission from a quantum cascade laser (QCL) is fundamental for exploitation this unique source in myriad applications where it can be implemented, such as spectroscopy, imaging, and sensing. Active control frequency, power, polarization, beam profile has been achieved through variety approaches. In particular, active emitted which difficult to determine priori, integration photonic structure and/or by using external cavity arrangements. work, an...

The growing interest in terahertz (THz) technologies recent years has seen a wide range of demonstrated applications, spanning from security screening, non-destructive testing, gas sensing, to biomedical imaging and communication. Communication with THz radiation offers the advantage much higher bandwidths than currently available, an unallocated spectrum. For this be realized, optoelectronic components capable manipulating at high speeds signal-to-noise ratios must developed. In work we...

The dynamically tunable terahertz (THz) waves and electromagnetically induced transparency (EIT) in coupled hybrid superconducting niobium-graphene split-ring resonator arrays are investigated. Active modulation of THz is studied through two different approaches. Thermal tuning amplitude group delay observed due to the temperature sensitivity niobium superconductor. Stronger photoresponses when superconducting. electrical integrated device accomplished integration graphene patches with...

We propose a synchronous implementation of compressive imaging. This method is mathematically equivalent to prevailing sequential methods, but uses static holographic optical element create spatially distributed spot array from which the image can be reconstructed with an instantaneous measurement. present design requirements and demonstrate experimentally that linear algebra compressed imaging implemented this technique. believe technique integrated metasurfaces, will allow development new...

Summary form only given. The continuous development of terahertz (THz) sources has opened up many potential applications in spectroscopy, imaging and communications. One popular THz source is the quantum cascade laser (QCL), which desirable properties including compactness high output power with a narrow emission frequency. For such to be successfully integrated into communication system, it necessary have control over amplitude, frequency phase. wireless purposes, amplitude modulators must...

Within the last years there has been a tremendous thrust into research and technology in THz spectral region (broadly defined as 0.1-10 THz) mainly driven by unique potential where this radiation finds applications in, such imaging, spectroscopy communication. In all these fields fast, integrated versatile platform for modulating light is required. Metamaterial/graphene devices fulfill requirements their subwavelength nature lends itself naturally to strong light-matter interaction,...

Terahertz (THz) science and technology has experienced tremendous progress in recent years, such as spectroscopy, imaging, pharmaceutical research <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</sup> wireless communications. These applications require electrically tuneable devices to modulate the THz properties, including amplitude, frequency polarization. The integration of resonant plasmonic/metamaterial with graphene, proved a successful...

Abstract Active control of chirality in the terahertz frequency range is great importance many scientific areas, which include research into fundamental optical phenomena, investigation novel materials, spectroscopy, imaging, wireless communications and chemistry. The lack efficient, integrated fast-reconfigurable polarization modulators has hindered, so far, full exploitation applications all aforementioned fields. Metamaterials are artificial resonant elements possessing unique remarkable...

An antenna-coupled dual-gated two-dimensional electron gas (2DEG) based on a GaAs-AlGaAs heterostructure shows pronounced response to 2 THz radiation. The device is shown be direct detector, and its photoresponse arises without any source-drain bias. detection novel mechanism that yields substantially stronger than predicted by the classical plasma-wave self-mixing other mechanisms.

We propose and demonstrate a new implementation of compressive imaging using diffractive optical element. This method is mathematically equivalent to existing sequential methods (Takhar et al. Proc. SPIE 6065, 2006), but utilises static element produces spatially distributed spot array. It envisaged that this could be used with metasurfaces perform instaneous hyperspectral polarisation-dependent imaging.