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Файл:Оптоэлектроника. Optoelectronics. Учебное пособие
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Quantum physics developed through the first half of the twentieth century
largely through work on our understanding of how photons and matter
interact and inter-relate. This was viewed, however, as a study of the matter
involved more than the light involved.
In 1953, the maser was developed which emitted coherent microwaves
and in 1960 the laser which emitted coherent light. As the property of the
light involved in these devices became more important, quantum optics began
being used as the term for this specialized field of study.
Quantum optics (and quantum physics as a whole) views electromagnetic
radiation as traveling in the form of both a wave and a particle at the same
time. This phenomenon is called wave-particle duality.
The most common explanation of how this works is that the photons
move in a stream of particles, but the overall behavior of those particles is
determined by a quantum wave function that determines the probability of the
particles being in a given location at a given time.
Taking findings from quantum electrodynamics (QED), it is also possible
to interpret quantum optics in the form of the creation and annihilation of
photons, described by field operators. The reaction in which a particle and its
antiparticle collide and disappear, releasing energy is termed as annihilation.
The most common annihilation on Earth occurs between an electron and its
antiparticle, a positron. A positron, which may originate in radioactive decay
or, more commonly, in the interactions of cosmic rays in matter, usually combines briefly with an electron to form a quasi-atom called positronium. Two
constituent particles of the quasi-atom spinning around each other are bound
to radiate two or three gamma rays as soon as they annihilate.
Photons of visible light are energetic enough to initiate some dramatic
chemical reactions, like photosynthesis, for example. The characteristic of
absorbing visible photons by semiconductor materials makes PV cells transform light energy to electric one.
Lasers (and masers) are the most obvious application of quantum optics.
Light emitted from these devices is in a coherent state, which means the light
closely resembles a classical sinusoidal wave. In this coherent state, the quantum mechanical wave function (and thus the quantum mechanical uncertainty) is distributed equally. The light emitted from a laser is, therefore,
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highly ordered, and generally limited to essentially the same energy state (and
thus the same frequency & wavelength).
READING COMPREHENSION
5 Answer the questions.
1. Which two field does quantum optoelectronics combine?
2. Which physical phenomena do constitute QED fields of study?
3. How can the same issues be interpreted by quantum optoelectronics
(QOE)?
4. When was the term itself photon came into being?
5. Whom does the idea of light emitted and absorbed in discrete bundles
belong to?
6. What is meant by physical process of annihilatation?
7. Which major applications does the quantum mechanical process of
stimulated emission respond to?
6 Which statement below best presents the essential information
in the text?
A The information presented introduces the field and the basic notions of
quantum optoelectronics (QOE).
B The information presented emphasizes the recent QOE applications in
the field.
C The information presented seems to cover most significant phases of
the discipline.
DEVELOPING VOCABULARY
7 Find the words from the box within the text.
spinning collide annihilate coherent radiate closely
For each word read the sentence it occurs in and answer the questions.
a) Is the word positive, negative, or neutral?
b) Is it a noun, adjective, or verb?
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c) Can you think of a word with a similar meaning and one with an opposite meaning?
READING COMPREHENSION
ANALYZE
8 Match the words and word collocations with their Russian equivalents.
1 the interaction of photons with
matter
2 any physical entity b квантово-волновой дуализм; корпус-
3 discrete bundles c любой физической обьект
4 blackbody radiation d излучать когерентные
5 the filament of a light bulb e в результате радиоактивного
6 emit coherent microwaves f излучать когерентный свет
7 originate in radioactive decay g взаимодействие фотонов с веще-
8 emit coherent light h дискретные пучки (света)
9 wave-particle duality i излучение в полости; равновесное
a нить накала электрической
лампочки
кулярно-волновой дуализм
микроволны
распада
ством
излучение; температурное
излучение абсолютно чёрного
тела
9 Give the Russian equivalents to:
1. behave as both particles and waves
2. act as field operators
3. a quantum wave function
4. determine the probability of the particles
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5. tiny sub-atomic particles
6. move in discrete bundles
7. release energy
8. gamma rays radiate from the point of collision
9. emit coherent microwaves
10. specialized field of study
10 Prove the following statements.
1. This phenomenon is called wave-particle duality.
2. After the annihilation of an electron-positron pair two or three gamma
rays radiate from the point of collision.
3. Light emitted from both laser and maser is in a coherent state.
11 Put the words into the correct order.
1. duality / phenomenon / held / called / a /is / This / a / wave-particle
2. most / masers / application /quantum /and / obvious/ are / the / Lasers /
of / optics
3. overall / photons / of / behavior / The / a / quantum / determined /
is / the / by / function / wave
4. wave / light / a / sinusoidal / classical / resembles / closely /The
12 Match the words with their definitions.
1 collide a to move in circles around an axis or center
2 spin b to set free (as from confinement)
3 annihilate c a comparatively short electromagnetic wave, esp. one
between about one millimeter and one meter in wavelength
4 release d resembling in some degree
5 antiparticle e to be out of harmony or agreement usually noticeably
6 sinusoidal f to eradicate, to destroy all traces of
7 coherent g relating to or composed of waves having a constant
difference in phase
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8 particle h a subatomic particle identical to another subatomic
particle in mass but opposite to it in electric and magnetic properties (such as sign of charge) that when
brought together with its counterpart produces mutual
annihilation
9 quasi- i any of the basic units of matter and energy (such as a
molecule, atom, proton, electron, or photon)
10 microwave j of, relating to, shaped like, or varying according to a
sine curve or sine wave
13 Match the words with their synonyms.
The word matter in the context is similar to the meaning of
(a) content
(b) subject
(c) substance
(d) issue
The word entity in the context is similar to the meaning of
(a) individual
(b) object
(c) substance
(d) integer
The word discrete in the context is similar to the meaning of
(a) free
(b) separate
(c) unattached
(d) single
The word probability in the context is similar to the meaning of
(a) liability
(b) likelihood
(c) possibility
(d) chance
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The word duality in the context is similar to the meaning of
(a) two different parts or elements
(b) two similar parts or elements
(c) two opposite parts or elements
(d) two parts or elements brought together
The word interact in the context is similar to the meaning of
(a) collaborate
(b) effect
(c) affect
(d) communicate
14 Complete the verbs with the prepositions, translate them into
Russian.
interact ___________________
travel___________________
refer___________________
radiate___________________
occur__________________
emit___________________
increase___________________
15 Fill in the gaps with the verbs from 12. Mind the correct form
of the verb.
1. The tests published reflect the way the sound …………………… an
empty room space.
2. All the members of the group have to …………………… more in-
stances to get proof for this hypothesis,
3. Heat …………………… the sun.
4. Heartburn is a burning pain in their chests that commonly these hours,
soon after eating.
5. The black body radiation spectral intensity peaks at a frequency to pro-
portionally…………………… the temperature of the emitter in accordance
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with the equation E = hf, with the approximate value of h of 6.626 × 10
−34
joule.
TRANSLATE
16 Translate from English into Russian.
1. The quantum Hall effect is a well-accepted theory in physics describing the behavior of electrons within a magnetic field at extremely low temperatures.
2. Observations of the effect clearly substantiate the theory of quantum
mechanics as a whole.
3. The results are so precise that the standard for the measurement of electrical resistance uses the quantum Hall effect, which also underpins the work
done on superconductors.
4. The Hall effect, discovered by Edwin Hall in 1879, is observed when
a current of electricity passes through a conductor placed in a magnetic field.
5. Charge carriers, which are usually electrons but can be protons, scatter
to the side of the conductor due to the influence of the magnetic field.
6. The phenomenon can be visualized as a series of cars pushed sideways
due to a strong wind while going down a highway.
7. The cars take a curved path as they attempt to drive forward but are
forced sideways.
8. A potential difference between the sides of the conductor develops.
9. The voltage difference is quite small and is a function of the composition of the conductor.
10. Amplification of the signal is necessary to make useful instruments
based on the Hall effect.
11. This imbalance in electrical potential is the principle behind a Hall
probe that measures magnetic fields.
17 Translate from Russian into English.
1. С ростом популярности полупроводников физики заинтересова-
лись исследованием эффекта Холла в настолько тонкой фольге, что носители заряда были ограничены движением
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в двух измерениях.
2. Они подавали ток на электропроводную фольгу в сильных магнитных полях при низких температурах.
3. Вместо того, чтобы отскакивать по сторонам по непрерыв-
ным изогнутым траекториям, электроны совершают внезапные
прыжки.
4. При изменении силы магнитного поля наблюдались резкие пики
сопротивления потоку на определенных уровнях энергии.
5. В промежутках между пиками
сопротивление падало до значения,
близкого к нулю, что характерно для низкотемпературных сверхпроводников.
6. Физики также поняли, что уровень энергии, необходимый для
возникновения скачка сопротивления, не зависит от состава проводника.
7. Пики сопротивления происходили в целых числах, кратных друг
другу.
8. Эти пики настолько предсказуемы и постоянны, что инстру-
менты, основанные на квантовом эффекте Холла, можно использовать
для создания эталонов сопротивления.
9. Такие стандарты необходимы для тестирования электроники и
обеспечения надежной работы.
10. Квантовая теория атомной структуры, согласно которой энергия
доступна в отдельных целых пакетах на субатомном уровне, предсказала квантовый эффект Холла еще в 1975 году.
11. В 1980 году Клаус
фон Клитцинг получил Нобелевскую премию
по физике за открытие того, что квантовый эффект Холла действительно является дискретным, то есть, электроны могут существовать
только на четко определенных уровнях энергии.
12. Квантовый эффект Холла стал еще одним аргументом в пользу
квантовой природы материи.
WORD BUILDING
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18 Write down the basic form of the derivatives.
Example:
collision – to collide
absorption .....................................................................
annihilation ..................................................................
application ....................................................................
interpretation ...............................................................
interaction ...................................................................
resemblance ..................................................................
behavior ........................................................................
probability ....................................................................
heating ..........................................................................
spinning ........................................................................
involved .......................................................................
Unit 2
GRAMMAR
19 Read the sentences to define the function of the infinitive.
Translate the sentences into the Russian language.
1. For example, the addition of less than 0.01 percent of a particular type
of impurity can increase the electrical conductivity of a semiconductor by
four or more orders of magnitude (i.e., 10,000 times).
2. In order to strengthen them, single crystals are typically hot-forged
to induce clean grain boundaries and large grain sizes, which do not decrease infrared transmission significantly but allow the body to resist deformation.
3. The process of epitaxy is general, however, and so can occur for other
classes of materials, such as metals and oxides, which have been used since
the 1980s to create materials that display giant magnetoresistance (a property
that has been used to produce higher-density digital storage devices).
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4. Examples include growth from thermally vaporized material such as
silicon or from gases such as silane (SiH4), which reacts with a hot surface to
leave behind the silicon atoms and to release the hydrogen back into the gaseous phase.
5. The main reasons for this are twofold: (1) silicon devices exhibit much
lower leakage currents, and (2) high-quality silicon dioxide (SiO2), which is
an insulator, is easy to produce.
6. To produce higher conduction, one can intentionally introduce impurities (typically to a concentration of one part per million host atoms).
7. Similarly, Figure 2C shows that, when an atom with three outer elec-
trons such as boron is substituted for a silicon atom, an additional electron is
“accepted” to form four covalent bonds around the boron atom.
8. Powdered pigments are incorporated into ceramic bodies or glazes in
order to impart colour to the fired ware.
9. The microprocessor enabled computer engineers to develop microcomputers‒systems about the size of a lunch box or smaller but with enough computing power to perform many kinds of business, industrial, and scientific
tasks.
10. However, if an atom from column V of the periodic table, such as phosphorus, is substituted for an atom of silicon, four of its five outer electrons will
be used for bonding, while the fifth will be free to move within the crystal.
20 Make use of either to-infinitive or bare infinitive.
1. On the chip, transistors act as miniature electrical switches that can
(turn) a current on or off.
2. The pattern of tiny switches is created on the silicon wafer by adding
and removing materials (form) a multilayered latticework of interconnected
shapes.
3. Unlike the metals normally used to conduct electrical currents, silicon
is a ‘semiconductor’, meaning that its conductive properties can (be increased) by mixing it with other materials such as phosphorus or boron.
4. A microchip the size of your fingernail contains billions of transistors,
so it’s easy (understand) just how small the features on a chip need to be.
5. There are two major ways (categorize) microchips: by functionality
and by type of integrated circuitry.
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