Robbins Mygind (massapple1)

Contrary to conventional Tamm plasmon (TP) absorbers of which narrow absorptance peaks will shift toward short wavelengths (blueshift) as the incident angle increases for both transverse magnetic (TM) and transverse electric (TE) polarizations, here we theoretically and experimentally achieve nonreciprocal absorption in a planar photonic heterostructure composed of an isotropic epsilon-near-zero (ENZ) slab and a truncated photonic crystal for TM polarization. This exotic phenomenon results from the interplay between ENZ and material loss. And the boundary condition across the ENZ interface and the confinement effect provided by the TP can enhance the absorption in the ENZ slab greatly. As a result, a strong and nonreciprocal absorptance peak is observed experimentally with a maximum absorptance value of 93% in an angle range of 60∼70°. Moreover, this TP absorber shows strong angle-independence and polarization-dependence. As the characteristics above are not at a cost of extra nanopatterning, this structure is promising to offer a practical design in narrowband thermal emitter, highly sensitive biosensing, and nonreciprocal nonlinear optical devices.Radio-over-fiber (ROF) link based on phase modulation and coherent detection has been widely proposed for linear transmission. Nowadays, there are increasing demands for long-distance analog radio-frequency (RF) signal transmission, as radars and broadcast systems. In this paper, a high spurious-free-dynamic-range (SFDR) analog coherent ROF link based on optical homodyne detection and genetic-algorithm-assisted digital demodulation is proposed and experimentally investigated. The ROF link is designed for transmitting RF signals ranging from 500 kHz to 100 MHz over a long-distance fiber under the environment of wide temperature. We test the link performance by transmitting different groups of two-tone signals (580 kHz and 600 kHz, 9 MHz and 10 MHz, 49 MHz and 50 MHz, 99 MHz and 100 MHz) over a 100.8-km single-mode fiber (SMF) under the temperature varying from -40°C to 70°C, the shot-noise-limited SFDR of the link are measured to be greater than 122 dB·Hz2/3.The mode multiplexing/de-multiplexing devices are key components for mode-division multiplexing (MDM) technology. Here, we propose an ultra-compact and reconfigurable mode-conversion device via inverse design, which can selectively implement multichannel mode conversion controlled by input phase shifts (Δφ). The device can transform input TE0 (TE1) mode to TE4 (TE3) mode at Δφ=0, or from TE0 (TE1) to TE1 (TE2) at Δφ=π spanning the wavelength range of 1525-1565 nm. We further demonstrate an integrated monolithic module based on the mode conversions to directly demodulate the dual-mode difference phase shift keying (DPSK) signal which significantly reduces the device size and benefits for future dense integrations in MDM systems.Optical communication wavelength is being extended from the near-infrared band of 1.31/1.55 µm to the mid-infrared band of 2 µm or beyond for satisfying the increasing demands for high-capacity long-distance data transmissions. An efficient electro-optic (EO) modulator working at 2 µm is highly desired as one of the indispensable elements for optical systems. Autophinib price Lithium niobate (LiNbO3) with a large second-order nonlinear coefficient is widely used in various EO modulators. Here, we experimentally demonstrate the first Mach-Zehnder EO modulator working at 2 µm based on the emerging thin-film LiNbO3 platform. The demonstrated device exhibits a voltage-length product of 3.67 V·cm and a 3-dB-bandwidth of >22 GHz which is limited by the 18 GHz response bandwidth of the photodetector available in the lab. Open eye-diagrams of the 25 Gb/s on-off keying (OOK) signals modulated by the fabricated Mach-Zehnder EO modulator is also measured experimentally with a SNR of about 14 dB.We propose and demonstrate a temperature-insensitive directional transverse load sensor based on a fiber Bragg gratin