Practical terahertz electronics : optical devices and applications / Vinod Kumar Khanna.

Format:

Book

Author/Creator:

Khanna, Vinod Kumar, author.

Series:

IOP Ebooks Series

Language:

English

Subjects (All):

Terahertz spectroscopy.

Physical Description:

1 online resource (260 pages)

Edition:

First edition.

Place of Publication:

Bristol, England : IOP Publishing, [2021]

Summary:

This research and reference text provides a comprehensive and authoritative survey of the state-of-the-art in terahertz electronics research. Volume two focuses on optical devices and their applications. Intended for researchers and professionals in the field, the text is an essential reference for anyone working at the cutting edge of terahertz electronics.

Contents:

Intro

Preface

Acknowledgements

Author biography

Vinod Kumar Khanna

Introduction

Academic qualifications

Work experience and accomplishments

Semiconductor facility creation and maintenance

Scientific positions held

Membership of professional societies

Foreign travel

Scholarships and awards

Research publications and books

About the Book

Abbreviations and acronyms

Chemical symbols

Mathematical notation

Greek alphabet

Chapter 1 Bolometers, Golay cells and pyroelectric detectors

1.1 Bolometers

1.2 Uncooled bolometers

1.2.1 Antenna-coupled bolometer

1.2.2 Nanostructured thin film absorber integrated bolometer

1.2.3 MEMS bolometer

1.3 Cooled superconducting bolometers

1.3.1 Limitations of SIS tunnel junction devices

1.3.2 Superconducting hot electron bolometer

1.3.3 Diffusion-cooled hot electron bolometer

1.3.4 Electron-phonon cooled hot-electron bolometer

1.4 Golay cell

1.5 Pyroelectric detector

1.5.1 Pyroelectricity

1.5.2 Pyroelectric current

1.5.3 Impermanency of pyroelectric voltage

1.5.4 Difference between pyroelectricity and thermoelectricity

1.5.5 Pyroelectric, piezoelectric and piezocaloric effects

1.5.6 Ferroelectric materials

1.5.7 Crystal classes and crystal behavior

1.5.8 Function of the pyroelectric detector

1.6 Discussion and conclusions

References

Chapter 2 Optical rectification and electrooptic effect-based components

2.1 Non-linear optics

2.2 Linear versus non-linear optics

2.3 Electromagnetic wave propagation in linear optical media

2.3.1 Maxwell's equations

2.3.2 Derivation of the wave equation for linear media

2.4 Electromagnetic wave propagation in non-linear optical media

2.4.1 Modification of the equation for induced polarization.

2.4.2 Modification of the wave equation for non-linear media

2.5 Second-order response of a non-linear medium to single-electromagnetic wave input

2.6 Visualization and observation of optical rectification

2.7 Second-order response of a non-linear medium to two-electromagnetic wave input

2.8 Second-order response of a non-linear medium to an ultrashort pulse of single-electromagnetic wave input

2.9 Detection of terahertz wave pulses

2.9.1 Electrooptic effects

2.9.2 Electrooptic phase modulator

2.9.3 Terahertz pulse detection by phase modulation of near infrared pulse

2.10 Discussion and conclusions

Chapter 3 Photoconductive antennas and photomixers

3.1 Photoconductive antenna

3.1.1 The short carrier lifetime, sufficient-carrier-mobility III-V compound semiconductor film

3.1.2 The microstrip lines, contact pads and dipole structure

3.1.3 The silicon lens

3.1.4 Typical dimensions

3.1.5 Generation of broadband pulses of terahertz wave

3.1.6 Mechanisms of terahertz pulse generation

3.1.7 Generation of narrowband continuous wave terahertz radiation

3.2 PCA time-domain spectroscopy system

3.3 Photomixer

3.3.1 Heterodyne principle

3.3.2 Construction of the photomixer

3.3.3 Photomixer arrangement for imaging or spectroscopy

3.4 Salient features of the PCA mixer

3.4.1 Power limitation

3.4.2 Radiation resistance of the antenna and R-C roll-off

3.5 Antenna-less large-area emitter approach of terahertz generation

3.6 Photomixer using UTC-PD

3.6.1 Unitravelling-carrier photodiode

3.6.2 UTC photomixer

3.7 Discussion and conclusions

Chapter 4 Quantum cascade and optically-pumped gas lasers

4.1 Features of semiconductor diode lasers and their failure to produce terahertz waves

4.2 Quantum cascade laser

4.2.1 QCL materials.

4.2.2 Principle of a quantum cascade laser

4.2.3 Frequency tunability of QCL

4.2.4 Unipolarity of QCL

4.2.5 Cryogenically-cooled THz QCLs

4.2.6 Obstacles to room-temperature terahertz production by QCL

4.2.7 Circumventing hindrances to room-temperature QCL operation

4.3 Optically-pumped methanol gas laser

4.3.1 Optical pumping

4.3.2 CO2 gas IR laser as optical pumping source

4.3.3 Methanol as active molecular medium being pumped

4.3.4 Energy-level scheme of methanol laser

4.3.5 Organization of optically-pumped methanol laser

4.3.6 Advantages and disadvantages of methanol laser

4.3.7 Optically-pumped gas laser as a high-power, compact and continuous-wave source of terahertz radiation

4.4 Discussion and conclusions

Chapter 5 Communication

5.1 Recapitulation of common communication terms and laws

5.1.1 Data rate or data transfer rate

5.1.2 Bandwidth

5.1.3 Bandwidth and speed

5.1.4 Throughput

5.1.5 Network capacity

5.1.6 Nyquist bit rate formula for a noiseless channel

5.1.7 Noise in channels

5.1.8 Shannon's law for a noisy channel

5.1.9 Bandwidth and capacity

5.1.10 Latency (s)

5.2 Effects of frequency of electromagnetic waves on their propagation characteristics, antenna dimensions and information-carrying capacity

5.2.1 The central role of frequency of communication signal

5.2.2 Pertinent questions

5.2.3 Ground waves

5.2.4 Sky waves

5.2.5 Space waves and satellite links

5.3 Atmospheric attenuation of space waves beyond 30 GHz microwaves towards terahertz waves

5.3.1 Absorption of microwaves by moisture and oxygen

5.3.2 Transmission windows for communication of sub-THz and THz waves

5.3.3 Signal transmission in outer space

5.4 Free space path loss

5.4.1 Definition and physical meaning.

5.4.2 Derivation of expression for FSPL from the Friis formula

5.5 Link budget analysis

5.5.1 Writing the link budget equation

5.5.2 dBm to Watts conversion

5.5.3 Logarithmic form of the link budget equation

5.5.4 Link margin

5.5.5 Symbolic form of the logarithmic link budget equation

5.6 Opportunities offered by terahertz waves for communications

5.6.1 Present allocation of the electromagnetic spectrum to communication signals

5.7 Biosafety and human health concerns on electromagnetic radiation exposure

5.7.1 Gamma and x-ray communication spectra

5.7.2 Visible light, infrared and terahertz spectra

5.8 Salient features of terahertz communication

5.8.1 Motivation for utilization of terahertz band for communication

5.8.2 Viable bandwidths

5.8.3 Provision of interference-free communication

5.8.4 Security of communication link

5.8.5 Creation of ultra-dense networks

5.8.6 Mobile fronthaul improvement and backhaul sustenance

5.9 Challenges posed/implementational difficulties of terahertz communication, and possible solutions

5.9.1 High path attenuation

5.9.2 Low penetration ability

5.9.3 Necessity of high-gain antennas

5.9.4 Frequency of outages

5.10 Optically- and electrically-driven terahertz wave modulators

5.10.1 Dependence of interaction of terahertz waves with a material on its electrical conductivity

5.10.2 Optical pumping

5.10.3 Electrical driving

5.10.4 Terahertz modulation by optical pumping

5.10.5 Terahertz modulation by electrical driving

5.11 Optically-pumped spatial modulator

5.12 Electrically-driven modulator using two-dimensional electron gas (2DEG)

5.13 Electrically-driven metamaterial-based modulator

5.14 Graphene modulators

5.14.1 Optically-pumped graphene modulator

5.14.2 Electrically-driven graphene modulator.

5.15 Discussion and conclusions

Chapter 6 Spectroscopy

6.1 Spectra and spectroscopies

6.1.1 Spectrum

6.1.2 Spectroscopy

6.1.3 Time and frequency domains

6.2 Scheme of terahertz TDS

6.2.1 THz-TDS concept

6.2.2 THz-TDS instrumentation system

6.3 Rotational and vibrational aspects of terahertz spectroscopy

6.4 Comparison of THz time-domain with far infrared Fourier transform spectroscopic techniques

6.5 Discussion and conclusions

Chapter 7 Imaging

7.1 Types of imaging

7.2 Close-range imaging techniques

7.2.1 Transmission and reflective pulse imaging by mechanical raster scanning

7.2.2 Reflective pulse imaging by inverse synthetic aperture method

7.2.3 2-D imaging of continuous wave terahertz radiation by electro-optic detection

7.3 Stand-off imaging techniques

7.3.1 Focal plane array (FPA) imaging

7.3.2 Interferometric imaging

7.4 Security surveillance

7.4.1 Explosives

7.4.2 Illicit drugs

7.5 Pharmaceutical products characterization

7.5.1 Polymorphism in crystalline drug materials

7.5.2 Modification of crystalline drug materials by hydration or salt formation

7.5.3 Spontaneous conversion of amorphous drug materials to more stable crystalline form

7.5.4 Coating films of tablets

7.6 Clinical diagnosis

7.6.1 Dentistry

7.6.2 Cancer

7.7 Food and agricultural products inspection

7.7.1 Foreign body detection

7.7.2 Toxic substance detection

7.7.3 Antibiotic detection

7.7.4 Microbial contamination detection

7.7.5 Moisture content quantification

7.7.6 Quality assurance

7.7.7 Uncovering adulteration

7.8 Non-destructive testing (NDT)

7.8.1 Pulse THz-TDS technique

7.8.2 Reflection 3D THz imaging system

7.8.3 The FMCW technique

7.9 Discussion and conclusions

References.

Notes:

Description based on publisher supplied metadata and other sources.

Description based on print version record.

Includes bibliographical references.

ISBN:

9780750348881

0750348887

OCLC:

1429722856