Читать книгу Fundamentals of Terahertz Devices and Applications - Группа авторов - Страница 4

1 Chapter 2Figure 2.1 (a) Sketch of a planar antenna printed on a dielectric substrate....Figure 2.2 Geometrical parameters of an elliptical lens.Figure 2.3 (a) Equivalent aperture on top of the elliptical lens antenna. (b...Figure 2.4 (a) Scheme of the critical angle calculation on an elliptical len...Figure 2.5 (a) Incident, reflected, and transmitted power density in a diele...Figure 2.6 Reference system for the evaluation of the far fields radiated by...Figure 2.7 (a) High transmission and high reflection region of a silicon mad...Figure 2.8 Parallel and perpendicular transmission coefficient for a lens ma...Figure 2.9 Synthesis of an elliptical lens from an extended hemispherical le...Figure 2.10 Sketch of the extended semi‐hemispherical lens antenna parameter...Figure 2.11 Directivity of an elliptical lens and an extended hemispherical ...Figure 2.12 Sketch of the silicon lens antenna fed by a leaky‐wave feed geom...Figure 2.13 Real and imaginary parts of the propagation constants k_lw of the...Figure 2.14 Input reflection coefficient of a waveguide loaded with a double...Figure 2.15 Sketch of the leaky‐wave feed with its main parameters. The red ...Figure 2.16 Amplitude and phase of the electric centered at a central freque...Figure 2.17 (a) Drawing of the basic parameters of the shallow lens antenna ...Figure 2.18 Optimum (a) taper angle θ_f and (b) lens thickness W as a fu...Figure 2.19 (a) The shallow lens of diameter D is defined by a corresponding...Figure 2.20 (a) Radius R and (b) height H of the lens as a function of the d...Figure 2.21 (a) Directivity and (b) Gaussicity achieved for the shallow lens...Figure 2.22 Reflection coefficient centered at a central frequency f for the...Figure 2.23 (a) Sketch of the membrane fabrication process that contains the...Figure 2.24 (a) Sketch of the fabrication process of the shallow silicon len...Figure 2.25 (a) Surface measured of the fabricated lens of D = 2.6 mm. The e...Figure 2.26 Photographs of different lens antenna prototypes fed by leaky‐wa...Figure 2.27 (a) Reflection and (b) transmission coefficient for a silicon le...

2 Chapter 3Figure 3.1 (a) Power spectrum from commercial EDFA mode‐locked laser. (b) Ti...Figure 3.2 Optical fiber absorption vs wavelength.Figure 3.3 (a) Near‐band‐edge absorption coefficient of GaAs at room tempera...Figure 3.4 (a) Fractional absorption vs epitaxial thickness for a GaAs layer...Figure 3.5 Residual electron concentration (black squares) and resistivity (...Figure 3.6 (a) Conventional 1550‐nm p–i–n photodiode. (b) Conventional MSM b...Figure 3.7 Simulation results for p–i–n InGaAs/InP photodiode, showing trans...Figure 3.8 Simulation results for the lifetime‐limited transfer function, an...Figure 3.9 Comparison between spectral responsivities of 1550‐nm InGaAs MSM‐...Figure 3.10 (a) Energy diagram of an MSM electrode structure with low bias a...Figure 3.11 (a) Cross‐sectional view of photoconductor illuminated from the ...Figure 3.12 (a) Equivalent circuit model for a photoconductive switch. (b) P...Figure 3.13 (a) Reflectance (R), transmittance (T), and absorbance (A) of a ...Figure 3.14 Comparison between calibrated SPD detector and a commercial pyro...Figure 3.15 Equivalent THz input power for the output signal of Figure 3.14 ...Figure 3.16 Comparison between SPD detector and commercial pyroelectric dete...Figure 3.17 THz optical responsivity of QMC detector after cross‐calibration...Figure 3.18 (a) Spectrum of two frequency‐offset DFB lasers measured with OS...Figure 3.19 (a) SEM photograph of MSM photomixer is located in the gap betwe...Figure 3.20 (a) Antenna on a dielectric substrate showing the rays trapped b...Figure 3.21 (a) Sketch of a dipole antenna with a stepped impedance low pass...Figure 3.22 (a) Sketch of a log‐spiral AE. The antenna (grey) and the photom...Figure 3.23 (a) Electric lines of force between two coplanar electrodes on a...Figure 3.24 Schematic of a THz time‐domain spectroscopy (TDS) setup in trans...Figure 3.25 (a) Typical normalized pulse trace and corresponding normalized ...Figure 3.26 THz power and optical‐to‐THz conversion efficiency for state‐of‐...Figure 3.27 (a) conventional p–i–n photodiode with the i‐region made of InGa...Figure 3.28 Photocurrent transfer function for UTC‐PD device structure param...Figure 3.29 (a) UTC‐PD fabricated at the gap of a bow‐tie antenna. (b) Fully...Figure 3.30 Comparison of UTC‐PD (NTT) and HHI p–i–n photodiode THz power re...Figure 3.31 (a) Schematic diagram of photoexcitation and recombination in an...Figure 3.32 Near‐infrared absorption spectrum of the GaAs with embedded ErAs...Figure 3.33 (a) Average THz power vs bias voltage for a photoconductive swit...Figure 3.34 (a) I–V characteristics of a waveguide integrated photodiode and...Figure 3.35 (a) Schematic of a fiber‐coupled THz‐TDS system and (b) a contin...Figure 3.36 Mobile communications network architecture.Figure 3.37 Main photonic‐based signal generation concept techniques.Figure 3.38 Ultra‐broadband wireless link with photonic‐based carrier wave g...Figure 3.39 (a) Eye‐patterns of the received PRBS = 2²³–1 at bit rate BR = 1...Figure 3.40 (a) Performance of 1550‐nm fiber‐coupled time‐domain spectromete...Figure 3.41 (a) THz pulse and (b) associated spectrum, for state‐of‐the‐art ...Figure 3.42 (a) Performance of 1550‐nm fiber‐coupled frequency‐domain spectr...Figure 3.43 (a) Block diagram of 780‐nm FDS spectrometer having a single‐wav...Figure 3.44 (a) Block diagram of 1550‐nm fiber‐based wavelength‐selective ph...

3 Chapter 4Figure 4.1 THz generation by photomixing.Figure 4.2 Photomixing in a photoconductor.Figure 4.3 Electrical model of a photoconductor coupled to a load admittance...Figure 4.4 (a) Electrical circuit at ω = ω_b and (b) ω = 0_.Figure 4.5 Photomixing experiment AC/DC decoupling using a Bias‐T.Figure 4.6 Small signal Equivalent circuit at ω_b.Figure 4.7 Schematic band diagram of a p–i–n photodiode.Figure 4.8 Schematic band diagram of a UTC photodiode.Figure 4.9 Electric model of a UTC photodiode.Figure 4.10 Equivalent circuit of an UTC photodiode at ω (G_L = 1/R_L)_.Figure 4.11 Heterodyne mixing in a photoconductor illuminated by an optical ...Figure 4.12 SEM picture of an ultrafast photoconductor based on interdigitat...Figure 4.13 LT‐GaAs planar photoconductor.Figure 4.14 Refracting facet UTC photodiode.Figure 4.15 TEM horn UTC photodiode.Figure 4.16 Waveguide UTC photodiode coupled to a planar antenna.Figure 4.17 LT GaAs optical cavity photoconductor.Figure 4.18 Calculated optical quantum efficiency versus active layer thickn...Figure 4.19 Experimental set‐up aimed at photoresponse measurement.Figure 4.20 Theoretical (solid line) and experimental (in squares) photoresp...Figure 4.21 Optical cavity LT‐GaAs photoconductor.Figure 4.22 Experimental set‐up. ECLD, external cavity laser diode; SOA, sem...Figure 4.23 Photocurrent as a function of optical power V_b = 3 V.Figure 4.24 Output power at f_B = and V_b = 3 V.Figure 4.25 Top view of a 6‐μm‐diameter photoconductor coupled to the impeda...Figure 4.26 SEM micrograph of an optical cavity LT‐GaAs photoconductor linke...Figure 4.27 Down conversion experimental‐set‐up.Figure 4.28 Conversion loss and (1/G0)² as a function of the optical power (Figure 4.29 Design of the nanostructured contact. (a) Geometry of the metall...Figure 4.30 Fabrication of the PD. (a, b) Schematic cross section of the fab...Figure 4.31 (a)SEM image of UTC‐PD integrated with CPW, and (b) SEM image of...Figure 4.32 Experimental comparison of photoresponse of UTC‐PD devices and R...Figure 4.33 RF power generated at 300 GHz by various B‐type photodiodes for ...Figure 4.34 SEM picture of an equiangular spiral antenna.Figure 4.35 Geometry of the TEM‐HA (a). Geometry of the monopole configurati...Figure 4.36 SEM picture of a THz Horn antenna.Figure 4.37 E‐plane radiation patterns of the TEM‐HA: comparison between exp...Figure 4.38 Different probes technologies: GGB probes (Picoprobes for wafer‐...Figure 4.39 (a) Experimental setup for photomixing at wafer‐level. (b) Photo...Figure 4.40 Frequency response example of a UTC‐PD [19].Figure 4.41 Frequency response example of and device linearity.Figure 4.42 Example of free space UTC‐PD measurement using a Schottky quasi‐...

4 Chapter 5Figure 5.1 Band to band absorption of a photon in a semiconductor, creating ...Figure 5.2 (a) Schematic of a PCA in operation. (b) Equivalent circuit model...Figure 5.3 Comparison between a short‐carrier‐lifetime and a long‐carrier‐li...Figure 5.4 Equivalent circuit model of a PCA‐based THz detector.Figure 5.5 Surface plasmon dispersion relation, showing that surface plasmon...Figure 5.6 Illustrations for (a) conventional and (b) plasmonic PCAs based o...Figure 5.7 Finite element simulation of the conventional photoconductor and ...Figure 5.8 (a) SEM images of the conventional (left) and plasmonic (right) P...Figure 5.9 (a) THz waveform measured by a conventional (red) and plasmonic (...Figure 5.10 PCAs with plasmonic light concentrators. (a) Device illustration...Figure 5.11 Pulsed THz generation and detection using PCAs with plasmonic co...Figure 5.12 CW THz generation using PCAs with plasmonic contact electrodes. ...Figure 5.13 (a) Device structure and SEM images of a large‐area plasmonic ph...Figure 5.14 Device structure and SEM images of a large‐area plasmonic photoc...Figure 5.15 Plasmonic PCAs with optical nanocavities. (a) Device schematic o...

5 Chapter 6Figure 6.1 (a) Conduction‐band lineup of a generic semiconductor QW and squa...Figure 6.2 Conduction‐band diagram of a representative bound‐to‐bound QC gai...Figure 6.3 Conduction‐band diagram of a representative superlattice QC gain ...Figure 6.4 Conduction‐band diagram of a representative resonant‐phonon THz Q...Figure 6.5 Real part of the dielectric constant ε and mode intensity pr...Figure 6.6 Metal–metal corrugated ridge DFB THz QC laser.Figure 6.7 Voltage‐tunable cw emission spectra measured at 15 K with the low...Figure 6.8 Temperature‐dependent LIV characteristics measured with the highe...Figure 6.9 (a) Schematic illustration of ISB relaxation between two QW subba...Figure 6.10 Dispersion of light in a polar crystal in the spectral vicinity ...Figure 6.11 Conduction‐band diagram of a resonant‐phonon THz QC gain medium ...Figure 6.12 (a) Photocurrent spectrum of a double‐step III‐nitride ISB photo...Figure 6.13 (a) Valence‐band lineup of the SiGe/Si QC active material of Dem...Figure 6.14 (a) Fabrication process developed in [81, 82] for the formation ...Figure 6.15 Conduction‐band lineup and squared envelope functions of the rel...

6 Chapter 7Figure 7.1 (a) Band structure of graphene and sketch of the possible optical...Figure 7.2 (a) Definition of parameters in a generic structure with N conduc...Figure 7.3 (a) Schematic of the reconfigurable region in a terahertz modulat...Figure 7.4 Experimental results in broadband modulator structures. (a) Trans...Figure 7.5 Structure of an electromagnetic‐cavity integrated graphene electr...Figure 7.6 Experimental results on electromagnetic‐cavity integrated modulat...Figure 7.7 Example work on graphene/metal‐hybrid metamaterial structures so ...Figure 7.8 Summary of results on graphene/meta‐hybrid metamaterials when cha...Figure 7.9 Graphene/metal‐hybrid metamaterials: transmission line equivalent...Figure 7.10 (a) Sketch of the analyzed graphene‐dielectric integrated metasu...Figure 7.11 Two proposed ways in which to alter the sensitivity of terahertz...Figure 7.12 Graphene‐based active terahertz filters. (a) Sketch of the devic...Figure 7.13 Simulated (a) and measured (b) terahertz transmittance versus fr...Figure 7.14 Deep‐subwavelength metamaterial phase modulators. (a) Sketch of ...Figure 7.15 Geometrical trade‐offs in deeply‐scaled metamaterials. The metal...Figure 7.16 (a) Schematic of a MoS₂/metal‐hybrid metamaterial structure. The...Figure 7.17 Experimental result in MoS₂/metal hybrid metamaterials. (a) Meas...Figure 7.18 Ultrafast dynamics in WSe₂ thin films. (a) OPTP measurements of ...Figure 7.19 (a) Schematic and (b) optical image of a graphene reflection‐mod...Figure 7.20 Principle of the imaging experiment using graphene‐modulator arr...Figure 7.21 (a) Map of “pixelated illumination” without an object: ΔR_i0

7 Chapter 8Figure 8.1 Plasma wave frequencies for different sample geometries. (a) Gate...Figure 8.2 Schematics of a FET as a THz detector (a); and the equivalent cir...Figure 8.3 Schematic representation of the plasma waves in different regimes...Figure 8.4 (a) Detected drain‐source signal as a function of the gate voltag...Figure 8.5 (a) Measured (squares) and calculated 0.2 THz drain response of 2...Figure 8.6 (a) Schematic illustration of FinFET device structure (the drain ...Figure 8.7 (a) 32 × 32 FPA chip complete die micrograph (2.9 × 2.9 mm²) and ...Figure 8.8 (a) Top‐view illustration of a typical graphene micro‐ribbon arra...Figure 8.9 (a) Room temperature responsivity as a function of the gate bias ...Figure 8.10 (a) Schematics of the encapsulated BLG FET (top) and optical pho...Figure 8.11 (a) BP atoms are arranged in puckered honeycomb layers bounded t...Figure 8.12 Scanning electron microscope (SEM) images of the top‐gated FETs ...Figure 8.13 (a) Plasma velocity in diamond 2DHG as a function of hole effect...Figure 8.14 DC voltage response to the THz voltage of the 0.01 V amplitude a...

8 Chapter 9Figure 9.1 State‐of‐the‐art of frequency multiplier sources at room temperat...Figure 9.2 Frequency multiplier vs comb‐generator.Figure 9.3 Frequency multiplier ideal matching network and optimization.Figure 9.4 JPL 400 GHz four‐anode doubler with substrate‐less technology (de...Figure 9.5 LERMA‐C2N demonstration model of the 600 GHz two‐anode balanced d...Figure 9.6 Currents and electrical fields in the vicinity of the diodes of a...Figure 9.7 Schematics of a sub‐millimeter wave frequency tripler using an an...Figure 9.8 Picture of a four‐anode 900 GHz balanced tripler (designed by A. ...Figure 9.9 Detail of the diode area of a the balanced 1.5 THz tripler with a...Figure 9.10 Currents and electrical fields in the vicinity of the diodes of ...Figure 9.11 DC capacitance Vs voltage (a) and DC resistance Vs. Voltage (b) ...Figure 9.12 GaAs electron mobility and resistivity as a function of the elec...Figure 9.13 Theoretical DC breakdown voltage as a function of the epilayer d...Figure 9.14 GaAs electron mobility as a function of the ambient temperature ...Figure 9.15 Variation of the space charge region for different frequencies o...Figure 9.16 Charge density within the epilayer for different operation condi...Figure 9.17 (a) Definition of the HFSS wave‐port at the exact location of th...Figure 9.18 Optimization of the diodes‐cell of a four‐anode frequency triple...Figure 9.19 JPL 1500 GHz doubler with JPL frame‐less membrane technology (de...Figure 9.20 JPL flight model of the 1.7–1.9 THz local oscillator chain for H...Figure 9.21 (a) Last stage frequency tripler used for the 1.6–1.7 and 1.7–1....Figure 9.22 (a) Detail of the diode area of the Herschel 1.9 THz frequency t...Figure 9.23 JPL 1.8–2.1 THz multiplier sources at room temperature measured ...Figure 9.24 SEM image of the 2.7 THz balanced frequency tripler chip mounted...Figure 9.25 State‐of‐the‐art of 2.5–2.7 THz solid‐state sources at room temp...Figure 9.26 Schematics of JPL 1.6 THz high power multiplier chain and test s...Figure 9.27 Picture of JPL 1.6 THz high power multiplier chain.Figure 9.28 Picture of JPL 1.6 THz frequency tripler. This Frequency tripler...Figure 9.29 Performance of JPL 1.6 THz frequency tripler. RF performance in ...Figure 9.30 Close‐up vertical view of the power‐combined 260–340 GHz frequen...Figure 9.31 Quad‐chip 260–340 GHz tripler designed by John Ward at Jet Propu...Figure 9.32 Picture of the bottom half of the power‐combined 900 GHz frequen...Figure 9.33 Schematics of an in‐phase power‐combined balanced frequency doub...Figure 9.34 Detail of the demonstration model of the 300 GHz frequency doubl...Figure 9.35 Photograph of a dual‐symmetry 190 GHz balanced frequency doubler...Figure 9.36 Dual symmetry 190 GHz balanced frequency doubler using UMS Schot...Figure 9.37 Dual symmetry 190 GHz balanced frequency doubler using UMS Schot...Figure 9.38 Detail of JPL on‐chip in‐phase power combined 490–560 GHz freque...Figure 9.39 Performance of JPL 490–560 GHz frequency tripler. Two PAs module...Figure 9.40 Detail of JPL on‐chip in‐phase power combined 550 GHz single inp...Figure 9.41 Schematics of JPL on‐chip in‐phase power combined 550 GHz quad‐c...Figure 9.42 Photograph of JPL high power 165–195 GHz frequency doubler featu...Figure 9.43 Photograph of JPL high power 165–195 GHz module featuring four W...

9 Chapter 10Figure 10.1 I–V and C–V characteristics of an ideal Schottky contact.Figure 10.2 Harmonic generation from nonlinear Q–V.Figure 10.3 The dependence of multiplication efficiency on f₀/f_c.Figure 10.4 C–V characteristics of a diode with φ = 0.85 V, .Figure 10.5 Doubler input and output power using the diode characteristics i...Figure 10.6 The dependence of input power and efficiency on φ.Figure 10.7 The dependence of input power and efficiency on .Figure 10.8 Schematic for determining series resistance.Figure 10.9 Evaluated resistance of GaN diode versus diode anode size.Figure 10.10 Flowchart of semiconductor device numerical simulation.Figure 10.11 GaN low field mobility.Figure 10.12 GaN electron velocity.Figure 10.13 (a) Schematic of epi‐structure used in simulation (b) an exampl...Figure 10.14 Simulated ionization integral and electric field vs. bias volta...Figure 10.15 Simulated I–V characteristics.Figure 10.16 Series resistance extracted from forward IV curves in Figure 10...Figure 10.17 Simulated capacitance–voltage characteristics.Figure 10.18 Transient V(t),I(t) characteristics.Figure 10.19 Transient P(t) characteristics corresponds to Figure 10.18.Figure 10.20 Power and nonlinear performance of 300 nm thick N⁻ layer ...Figure 10.21 Power and nonlinear performance of 1 × 10¹⁷ cm⁻³ doped N⁻...Figure 10.22 Power and nonlinear performance of 1 × 10¹⁷ cm⁻³ doped 30...Figure 10.23 Power and nonlinear performance of 1 × 10¹⁷ cm⁻³ doped 30...Figure 10.24 SEM images of etched mesa by (a) Ar sputtering only in RIE and ...Figure 10.25 IV characteristics of Ni/GaN Schottky contact in forward region...Figure 10.26 Devices realized in this study.Figure 10.27 I–V characteristics of diodes with various diameter.Figure 10.28 Simulated current density contour of a diode.Figure 10.29 Cross section of GaN Schottky diode and the corresponding equiv...Figure 10.30 De‐embedding structures and the corresponding equivalent circui...Figure 10.31 Extracted C_{Y 12} from both as‐measured and de‐embedded Y‐paramet...Figure 10.32 Extracted C_{Y 12} versus bias voltage.Figure 10.33 Flow chart of EC modeling based on small‐signal S‐parameters.Figure 10.34 Extracted intrinsic parameters of diodes diameter from 2.5 to 1...Figure 10.35 Calculated cutoff frequency from extracted C_j and R_s.Figure 10.36 Simplified block schematic of sampler‐based LSNA.Figure 10.37 Configuration of measurement with 50 Ω.Figure 10.38 (a) Typical time‐domain waveform in I–V plot; (b) Q–V relation ...Figure 10.39 Derived instant Capacitance–Voltage relationship (solid lines),...Figure 10.40 Power handling capability for (a) 300 nm thick N⁻ layer (...Figure 10.41 Large‐signal diode model schematic for GaN Schottky diodes.Figure 10.42 P _out (dBm) versus P_absorbed (dBm). Symbols with solid lines:...Figure 10.43 Flow chart of large‐signal modeling for GaN Schottky diodes.Figure 10.44 Block diagram of a single diode frequency doubler.Figure 10.45 Schematic of large‐signal model of the 10 μm diode.Figure 10.46 S ₂₁ of the diode and with the presence of stubs.Figure 10.47 Schematic of circuit setup used for combining harmonic balance ...Figure 10.48 Simulated results of the 10 μm diode biased at −10 V, input pow...Figure 10.49 First (j₁) and third (j₃) harmonic amplitudes of the current os...Figure 10.50 Performance comparison between the state‐of‐the‐art measured ef...Figure 10.51 Current noise spectral density of single diodes in GaN‐ and GaA...Figure 10.52 (a) Forward I–V and fitting with TE in the low voltage range; (...

10 Chapter 11Figure 11.1 Current status of semiconductor single sources in THz range; out...Figure 11.2 Operation principle of RTD. (a) Layer structure, (b) Fermi spher...Figure 11.3 Fundamental structure of RTD oscillator. (a) RTD with slot reson...Figure 11.4 Electron movement with delay time in RTD.Figure 11.5 Structure of RTD oscillators. (a) Structure of fabricated planar...Figure 11.6 Structure and I–V characteristics of RTD. (a) Layer struct...Figure 11.7 Schematic illustration of decrease of NDC with frequency indicat...Figure 11.8 Oscillation characteristics of RTD oscillators with different th...Figure 11.9 Schematic illustration of slot antenna and RTD with equivalent c...Figure 11.10 Oscillation characteristics of RTD oscillators with and without...Figure 11.11 Parasitic elements around RTD. (a) Parasitic elements with sche...Figure 11.12 (a) Offset slot antenna for high output power and (b) theoretic...Figure 11.13 Array configuration of RTD oscillators for high output power. (...Figure 11.14 Large‐scale array and output power. (a) Oscillator element of l...Figure 11.15 PLL system of an RTD THz oscillator. (a) Block diagram, (b) dow...Figure 11.16 Frequency‐tunable RTD oscillator integrated varactor diode. (a)...Figure 11.17 Array configuration of frequency‐tunable oscillators for wide t...Figure 11.18 Direct modulation of RTD oscillator. (a) Measurement setup and ...Figure 11.19 Wireless data transmission using direct modulation of RTD oscil...Figure 11.20 Wireless data transmission with frequency or polarization divis...Figure 11.21 Absorbance of allopurinol measured by frequency‐tunable RTD osc...Figure 11.22 N‐element antenna array. Each element is assumed to have its ow...

11 Chapter 12Figure 12.1 Link budget (L_{dB}) and FSPL up to 1 THz [3], with antenna gain...Figure 12.2 Frequency bands and atmospheric attenuation. The frequency range...Figure 12.3 (a) Outdoor THz experiments: left: communication at 125 GHz over...Figure 12.4 State of the art of THz sources.Figure 12.5 GaAs Schottky diode‐based direct detection embedded in hollow wa...Figure 12.6 Architectures of the first THz wireless links. Several approache...Figure 12.7 Photomixing process for THz generation. Two optical signals are ...Figure 12.8 (a) SEM view of a UTC‐PD photomixer [24]. (b) Power level genera...Figure 12.9 UTC‐PD photomixer combination [25], reaching 1.2 mW at 300 GHz....Figure 12.10 Complex THz modulation using photomixing technique.Figure 12.11 Multifrequency generation of THz signals using photomixing.Figure 12.12 Solid‐state and TWT power‐levels as function of carrier frequen...Figure 12.13 Representation of the current performance of THz communication ...Figure 12.14 Transmission channels in IEEE 802.15.3d format.

12 Chapter 13Figure 13.1 The increased interest in THz technology is apparent from recent...Figure 13.2 A prototype THz instrument for exploring the atmosphere and wate...Figure 13.3 The availability of planar Schottky diodes has made it possible ...Figure 13.4 A number of different technologies can possibly be used as local...Figure 13.5 A compilation of measured output power from various multiplied s...Figure 13.6 An all‐solid‐state receiver to 1200 GHz has been demonstrated. B...Figure 13.7 A Nb SIS chip fabricated on SOI wafer and packaged in a split wa...Figure 13.8 Recent measurements on high current density SIS receiver. The br...Figure 13.9 Comparison of the frequency‐dependent loss of different supercon...Figure 13.10 Measured sensitivity of SIS, HEB, and SBD is compared along wit...Figure 13.11 Measured D/H ratios indicate a large range for comets with only...Figure 13.12 A two‐pixel 340 GHz. (a) show the full assembly with WR‐8 input...Figure 13.13 W‐band GaN power amplifiers make it possible to design 1.9 THz ...Figure 13.14 A compact 16‐pixel LO chain has been built with diagonal horns ...Figure 13.15 Nominal power requirement of 10 microwatts is demonstrated acro...Figure 13.16 A nominal block diagram for an active instrument that can measu...