A phased-array MASER detector for synthetic aperture interferometric three-dimensional imaging. The detector elements, for example 10.sup.2-10.sup.6 zero bias Schottky detector diodes with sufficient sensitivity to reliably detect various values of MASER radiation, are arranged in layers offset in three dimensions. The phased-array MASER detector is particularly useful for detecting characteristics in a biological object using low energy (2-10 Watts), coherent MASER radiation. MASER intensity data of an interferometric pattern is collected by the detector array, is deconvolved, and is used to generate three-dimensional energy activity maps for a given time slice or on a time-shifting basis.

A phased-array MASER detector for synthetic aperture interferometric three-dimensional imaging. The detector elements, for example 10.sup.2-10.sup.6 zero bias Schottky detector diodes with sufficient sensitivity to reliably detect various values of MASER radiation, are arranged in layers offset in three dimensions. The phased-array MASER detector is particularly useful for detecting characteristics in a biological object using low energy (2-10 Watts), coherent MASER radiation. MASER intensity data of an interferometric pattern is collected by the detector array, is deconvolved, and is used to generate three-dimensional energy activity maps for a given time slice or on a time-shifting basis.

A room-temperature semiconductor maser, including a first matching network, a second matching network, a heterojunction-containing transistor, and a resonant network. The output end of the first matching network is connected to the drain of the heterojunction-containing transistor. The input end of the second matching network is connected to the source of the heterojunction-containing transistor. The gate of the heterojunction-containing transistor is connected to the resonant network. The pumped microwaves are fed into the input end of the first matching network.

A photonic millimeter-wave oscillator is based on a heterodyne beatnote of two continuous wave lasers and is configured to provide a narrow linewidth output when the frequency difference is disciplined with rotational spectroscopy of molecules using frequency modulation spectroscopy.

Low power MASER (Microwave Amplification by Stimulated Emission of Radiation) radiation is used to non-invasively record molecular activity in a biological object such as a brain. Low power MASER radiation is also used to neuromodulate molecular targets via Rabi coupling, resulting for example in conformational and function change in specific molecular targets such as ligand-gated ion channels, voltage-gated ion channels, G-proteins, or dopamine receptors. The method can be used to change the energy state of targeted molecules via energization or enervation, or to ablate targeted molecules.

Low power MASER (Microwave Amplification by Stimulated Emission of Radiation) radiation is used to non-invasively record molecular activity in a biological object such as a brain. Low power MASER radiation is also used to neuromodulate molecular targets via Rabi coupling, resulting for example in conformational and function change in specific molecular targets such as ligand-gated ion channels, voltage-gated ion channels, G-proteins, or dopamine receptors. The method can be used to change the energy state of targeted molecules via energization or enervation, or to ablate targeted molecules.

An apparatus for novel technique of high-speed magnetic recording based on manipulating pinning layer in magnetic tunnel junction-based memory by using terahertz magnon laser is provided. The apparatus comprises a terahertz writing head configured to generate a tunable terahertz writing signal and a memory cell including a spacer that comprises a thickness configured based on Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction. The memory cell comprises two separate memory states: a first binary state and a second binary state; wherein the first binary memory state corresponds to a ferromagnetic sign of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction corresponding to a first thickness value of the spacer; and wherein the second binary memory state corresponds to an antiferromagnetic sign of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction corresponding to a second thickness value of the spacer. The thickness of the spacer is manipulated by the tunable terahertz writing signal.

A continuous optical beat laser element for generating terahertz (THz) waves and a laser source using same includes periodically poled lithium niobate (ppLN) crystals arranged along a predetermined direction forming a surface generally parallel to the predetermined direction. A Ti diffused region is applied on the surface and an array of gold nanowires are applied on the Ti diffused region to form a gold metal-insulator-metal (MIM) element that optimizes coupling and channeling of THz radiation from the crystals into the gold nanowires. The system provides a simple, stable, compact and cost-effective THz source using a widely tunable C-band SOA-based laser to excite a non-linear photo-mixer to produce terahertz radiation that ranges from 0.8 to 2.51 THz at room temperature. This laser source can be modified into an all fiber-based THz generator by embedding ppLN crystals in a fiber filament configuration resulting in less absorption and producing high output power.

A continuous optical beat laser element for generating terahertz (THz) waves and a laser source using same includes periodically poled lithium niobate (ppLN) crystals arranged along a predetermined direction forming a surface generally parallel to the predetermined direction. A Ti diffused region is applied on the surface and an array of gold nanowires are applied on the Ti diffused region to form a gold metal-insulator-metal (MIM) element that optimizes coupling and channeling of THz radiation from the crystals into the gold nanowires. The system provides a simple, stable, compact and cost-effective THz source using a widely tunable C-band SOA-based laser to excite a non-linear photo-mixer to produce terahertz radiation that ranges from 0.8 to 2.51 THz at room temperature. This laser source can be modified into an all fiber-based THz generator by embedding ppLN crystals in a fiber filament configuration resulting in less absorption and producing high output power.

An apparatus for generation of coherent terahertz radiation is provided. In one example, the apparatus includes one or more multilayer tunable microcolumns. In turn, a multilayer tunable microcolumn can include a substrate, a bottom electrode, a bottom layer of a ferromagnetic material further comprising a magnon gain medium (MGM) coupled to the bottom electrode, a tunnel junction coupled to the ferromagnetic material, a spin injector coupled to the tunnel junction, a pinning layer coupled to the spin injector, a reference layer coupled to the pinning layer and a top electrode. In one example, a containment cavity encloses at least one of the multilayer tunable microcolumns. In one example, a storage cavity encloses the containment cavity.