Metasurface Terahertz Perfect Absorber with Strong Multi-Frequency Selectivity.

In this paper, we design a metasurface terahertz perfect absorber with multi-frequency selectivity and good incident angle compatibility using a double-squared open ring structure. Simulations reveal five selective absorption peaks located at 0-1.2 THz with absorption 94.

Tunable and coherent terahertz source based on CdSiP crystal via collinear difference frequency generation.

CdSiP (CSP) crystals have attracted increasing attention as efficient optical conversion media. Herein, the optical properties of a CSP crystal grown with the vertical Bridgman method are measured by a terahertz time-domain spectrometer (THz-TDS) at 0.2-3 THz.

Terahertz dispersion using multi-depth phase modulation grating.

We present a multi-depth phase modulation grating (MPMG) in the terahertz range making real-time multichannel Fourier-transform spectroscopy available in a stationary manner. The calculation of the Fraunhofer diffraction field distribution and diffraction efficiency of an MPMG indicates that the zeroth-order diffraction light of an MPMG carries phase information and its diffraction intensity is modulated by the groove depth. A good agreement is found between the measurements of the 0th- and ±1st-order diffraction efficiency at 0.

Terahertz communication windows and their point-to-point transmission verification.

Terahertz communication is recognized as a transformational technology that can meet the future demands of point-to-point communication. The study of terahertz atmospheric transmission characteristics is important for guiding the terahertz communication window selection process. In this report, based on the modified ITU-R P.

Terahertz communication windows and their point-to-point transmission verification: publisher's note.

This publisher's note amends the author affiliations in Appl. Opt.57, 7673 (2018)APOPAI0003-693510.

Directly tailoring photon-electron coupling for sensitive photoconductance.

The coupling between photons and electrons is at the heart of many fundamental phenomena in nature. Despite tremendous advances in controlling electrons by photons in engineered energy-band systems, control over their coupling is still widely lacking. Here we demonstrate an unprecedented ability to couple photon-electron interactions in real space, in which the incident electromagnetic wave directly tailors energy bands of solid to generate carriers for sensitive photoconductance.

Extreme Sensitivity of Room-Temperature Photoelectric Effect for Terahertz Detection.

Extreme sensitivity of room-temperature photoelectric effect for terahertz (THz) detection is demonstrated by generating extra carriers in an electromagnetic induced well located at the semiconductor, using a wrapped metal-semiconductor-metal configuration. The excellent performance achieved with THz detectors shows great potential to open avenues for THz detection.

High performance of Mn-Co-Ni-O spinel nanofilms sputtered from acetate precursors.

Mn-Co-Ni-O (MCN) spinel oxide material, a very important transition metal oxide (TMO) with the best application prospects in information and energy fields, was discovered over five decades ago, but its applications have been impeded by the quality of its films due to the magnitude of deposition challenge. Here we report that high quality of MCN nanofilms can be achieved by sputtering deposition via acetate precursors whose decomposition temperatures are matched to the initial synthesis temperature of the MCN thin films. Excellent performance of MCN nanofilms is demonstrated, combining for the first time preferred orientation, high temperature coefficient of resistance, and moderate resistivity.

Room-temperature photoconductivity far below the semiconductor bandgap.

A concept to stimulate photoconductivity in a semiconductor well below its bandgap in a metal-semiconductor-metal structure with sub-wavelength spacing is proposed. A potential well is induced in the semiconductor by external electromagnetic radiation to trap carriers from the metals. This opens an avenue to generate carriers by photons without adequate excitation energy and is expected to have great significance in modern materials.