A terahertz device includes a terahertz element, a sealing resin, a wiring layer and a frame-shaped member. The terahertz element that performs conversion between terahertz waves and electric energy. The terahertz element has an element front surface and an element back surface spaced apart from each other in a first direction. The sealing resin covers the terahertz element. The wiring layer is electrically connected to the terahertz element. A frame-shaped member is made of a conductive material and arranged around the terahertz element as viewed in the first direction. The frame-shaped member has a reflective surface capable of reflecting the terahertz waves.

Provided is a multi-source signal generator including a voltage-controlled oscillator configured to generate a first source signal having a first frequency to deliver the first source signal to a first output port, a Single Pole Double Throw (SPDT) switch configured to select the first source signal or an external source signal, a first power amplifier configured to amplify power of the first source signal selected by the SPDT switch, and a multi-source converting unit configured to multiply a frequency of the amplified first source signal or divide power of the amplified first source signal to generate multi-source signals, wherein the frequency of the first source signal and frequencies of the multi-source signals are included in a millimeter wave band or sub-terahertz (THz) band.

The apparatus comprises a first coupler configured to receive two output signals, having 180 phase difference, outputted from a first differential generator as two input signals, and output a first voltage signal generated by adding the two input signals and a second voltage signal corresponding to subtraction of the two input signals, a second coupler configured to receive two output signals, having 180 phase difference, outputted from a second differential generator as two input signals, and output a third voltage signal generated by adding the two input signals and a fourth voltage signal corresponding to subtraction of the two input signals, a coupling network connected to the first differential generator and the second differential generator and a third coupler configured to output a signal generated by adding the voltage signal outputted from the first coupler and corresponding voltage signal outputted from the second coupler.

An ion-based atomic clock comprising an ion trap configured to trap a plurality of ions; and a micro-resonator-based frequency comb configured to directly drive a terahertz transition between metastable levels in the trapped plurality of ions. The micro-resonator-based frequency comb may be configured to directly drive a 24 terahertz transition in at least one Ba.sup.+ ion, a 8.4 terahertz transition in at least one Sr.sup.+ ion, or a 1.8 terahertz transition in at least one Ca.sup.+ ion. The micro-resonator-based frequency comb may be configured to provide output similar to a pulsed laser. The ion-based atomic clock may be free of a carrier-offset-stabilized frequency comb. The ion-based atomic clock may comprise a mini-vacuum ion trap assembly. Polarization of the micro-resonator-based frequency comb may be tuned to make the ion-based atomic clock be insensitive to laser light power fluctuations.

THz device includes: a semiconductor substrate; a first semiconductor layer disposed on the semiconductor substrate; an active element formed by being laminated on the first semiconductor layer; a second electrode connected to the first semiconductor layer to be connected to a cathode K of the active element, the second electrode disposed on the semiconductor substrate; a first electrode connected to an anode A of the active element, the first electrode disposed on the semiconductor substrate to be opposite to the second electrode; a rear reflector metal layer disposed on a back side surface of the semiconductor substrate opposite to the first semiconductor layer, wherein the active element forms a resonator between the second and first electrodes, wherein electromagnetic waves are reflected on the rear reflector metal layer, and electromagnetic waves have a surface light-emission radiating pattern or surface light-receiving pattern in a vertical direction to the semiconductor substrate.

A terahertz device includes a base member, a terahertz element, an antenna base, and a reflection film. The terahertz element is mounted on the base member and configured to generate an electromagnetic wave. The antenna base is located opposing the base member and includes an antenna surface. The reflection film is formed on the antenna surface to reflect at least part of the electromagnetic wave generated by the terahertz element in one direction.

A terahertz device includes: a support substrate; a terahertz element that is mounted to the support substrate and that emits an electromagnetic wave in a terahertz band; and a reflection body that is disposed on the opposite side to an element rear surface with respect to an element main surface in a z direction and at an interval in the z direction from the element main surface and that has a reflection surface for reflecting, in a direction crossing the z direction, an electromagnetic wave emitted in the z direction by the terahertz element.

The THz device module includes: a substrate; a THz device disposed on a front side surface of the substrate, and configured to oscillate or detect THz waves; a cap covering the THz device being separated from the THz device, and comprising an opening formed at a position opposite to the THz device in a vertical direction of the front side surface of the substrate; and a sealing member covering the opening of the cap so as to seal the THz device in conjunction with the substrate and the cap. A distance from the THz device to the sealing member is within a near-field pattern to which an electric field of the THz waves can be reached without interruption from a surface of the THz device to the sealing member. The THz device module efficiently emits or detects THz waves from the opening, thereby suppressing upsizing of the cap.

Provided is a terahertz-band electromagnetic wave oscillation element that includes an independent terahertz wave oscillation unit for oscillating terahertz-band electromagnetic waves. The terahertz wave oscillation unit consists of a discoid superconductor having a multilayered Josephson junction that enables oscillation of the terahertz-band electromagnetic waves by coordinated vibration of a plurality of Josephson junctions using an AC Josephson effect, the superconductor being circular in a cross section parallel to a lamination plane of the multilayered Josephson junction.

Provided is a multi-source signal generator including a voltage-controlled oscillator configured to generate a first source signal having a first frequency to deliver the first source signal to a first output port, a Single Pole Double Throw (SPDT) switch configured to select the first source signal or an external source signal, a first power amplifier configured to amplify power of the first source signal selected by the SPDT switch, and a multi-source converting unit configured to multiply a frequency of the amplified first source signal or divide power of the amplified first source signal to generate multi-source signals, wherein the frequency of the first source signal and frequencies of the multi-source signals are included in a millimeter wave band or sub-terahertz (THz) band.