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Plasmonics allows for an unmatched miniaturization. Along with the shrinking comes power efficient operation. Here, we show how plasmonics allows for an unprecedented downscaling of the classical MEMS and even of emerging memristive approaches. Ultimately, we will demonstrate optical elements at the atomic scale.

Plasmonics allows for an unprecedented miniaturization of optical elements. For instance, by combining plasmonics with memristive approaches atomic scale switches and photodetectors can be obtained, whereas combining plasmonics with MEMS allows realization of nano-opto-electro-mechanical switches.

Metal-dielectric platelets are introduced as additives to heat protection systems. The platelets feature high reflectivity across 700 nm and thermal stability up to 1000°C. Impregnating aerospace heat shields improves thermal reflectivity by a factor 11.

Here we show electrochemical metallization cells with compact dimensions, excellent electrical performance, and reproducible characteristics. An advanced technology platform has been developed to obtain Ag/SiO2/Pt devices with ultra-scaled footprints (15 × 15 nm2), inter-electrode distances down to 1 nm, and a transition from the OFF to ON resistance state relying on the relocation of only few atoms. This technology permits a well-controlled metallic filament formation in a highly confined field at the apex of an atomic scale tip. As a consequence of this miniaturization process, we achieve set voltages around 100 mV, ultra-fast switching times of 7.5 ns, and write energies of 18 fJ. Furthermore, we demonstrate very good cell-to-cell uniformity and a resistance extinction ratio as high as 6 · 105. Combined ab-initio quantum transport simulations and experiments suggest that the manufactured structures exhibit reduced self-heating effects due to their lower dimensions, making them very promising candidates as next-generation (non-)volatile memory components.

A compact and high-speed integrated photoconductive plasmonic photodetector is demonstrated. The proposed photodetector features a bandwidth beyond 100 GHz with an internal quantum efficiency of 36% around 1310 nm.

We show that Ohmic losses in plasmonic modulators can be bypassed by using a resonant scheme. This enables the first modulator that unites low-loss, high-speed, compact footprint and low-electrical energy consumption.

We show that Ohmic losses in plasmonic modulators can be bypassed by using a resonant scheme. This enables the first modulator that unites low-loss, high-speed, compact footprint and low-electrical energy consumption.

For nearly two decades, researchers in the field of plasmonics1—which studies the coupling of electromagnetic waves to the motion of free electrons near the surface of a metal2—have sought to realize subwavelength optical devices for information technology3,4,5,6, sensing7,8, nonlinear optics9,10, optical nanotweezers11 and biomedical applications12. However, the electron motion generates heat through ohmic losses. Although this heat is desirable for some applications such as photo-thermal therapy, it is a disadvantage in plasmonic devices for sensing and information technology13 and has led to a widespread view that plasmonics is too lossy to be practical. Here we demonstrate that the ohmic losses can be bypassed by using ‘resonant switching’. In the proposed approach, light is coupled to the lossy surface plasmon polaritons only in the device’s off state (in resonance) in which attenuation is desired, to ensure large extinction ratios between the on and off states and allow subpicosecond switching. In the on state (out of resonance), destructive interference prevents the light from coupling to the lossy plasmonic section of a device. To validate the approach, we fabricated a plasmonic electro-optic ring modulator. The experiments confirm that low on-chip optical losses, operation at over 100 gigahertz, good energy efficiency, low thermal drift and a compact footprint can be combined in a single device. Our result illustrates that plasmonics has the potential to enable fast, compact on-chip sensing and communications technologies.

A compact and high-speed integrated photoconductive plasmonic photodetector is demonstrated. The proposed photodetector features a bandwidth beyond 100 GHz with an internal quantum efficiency of 36 % around 1310 nm.

Photodetectors compatible with CMOS technology have shown great potential in implementing active silicon photonics circuits, yet current technologies are facing fundamental bandwidth limitations. Here, we propose and experimentally demonstrate for the first time a plasmonic photodetector achieving simultaneously record-high bandwidth beyond 100 GHz, an internal quantum efficiency of 36% and low footprint. High-speed data reception at 72 Gbit/s is demonstrated. Such superior performance is attributed to the subwavelength confinement of the optical energy in a photoconductive based plasmonic-germanium waveguide detector that enables shortest drift paths for photogenerated carriers and a very small resistance-capacitance product. In addition, the combination of plasmonic structures with absorbing semiconductors enables efficient and highest-speed photodetection. The proposed scheme may pave the way for a cost-efficient CMOS compatible and low temperature fabricated photodetector solution for photodetection beyond 100 Gbit/s, with versatile applications in fields such as communications, microwave photonics, and THz technologies.

We demonstrate a new concept of a photoconductive plasmonic photodetector that features high speed at nanometer scale. The concept is based on the electro-absorption effect in an plasmonic slot-waveguide with amorphous Ge as active material.

The arrival of the Single-Atom Transistor (SAT) in 2004, a quantum device operated at room temperature, allowed for the first controlled switching of an electrical current by the reproducible relocation of one single metal atom [1]. At the same time this component established the feasibility of transistors completely made of metals. Meanwhile, many experiments have followed, demonstrating the control of this three-terminal device on the atomic level and even showing a first simple integrated circuit [2]-[4]. A comparable device for plasmonic switching has not been realized yet. However, the fact that this Single Atom Transistor is made of silver - which is an ideal metal for plasmonics - opens intriguing perspectives for combining electronic and plasmonic switching in one and the same device at the atomic level. In this paper, we will demonstrate that photonic scaling is only limited by the atom. In particular we will present a novel plasmonic switch and photodetector featuring digital response at atomic scale. The principle of operation is based on the light-atom interaction in a memristive filament [5].

This paper gives an overview on the design, fabrication, and characterization of quantum cascade detectors. They are tailorable infrared photodetectors based on intersubband transitions in semiconductor quantum wells that do not require an external bias voltage due to their asymmetric conduction band profile. They thus profit from favorable noise behavior, reduced thermal load, and simpler readout circuits. This was demonstrated at wavelengths from the near infrared at 2 μm to THz radiation at 87 μm using different semiconductor material systems.