Soluzioni alle domande degli esami di Solid State Physics - digitali (apple pencil)

Questions solid

state physics

1

2

3

:

15 - The base vectors of the reciprocal lattice and their connection with the base vectors of the

corresponding real lattice

- The properties of the reciprocal lattice

76 - Miller indexes

17 Diffraction

: - X-rays, neutrons and electrons: discuss the kind of information that they can give if used as probes

in diffraction experiments

- The Von Laue condition for diffraction

- The Bragg condition and its physical assumptions (and why they are not reasonable)

20 - Equivalence of Von Laue and Bragg condition

21 - The Ewald sphere and the various kind of diffraction experimental techniques

22 Lattice oscillations

- The dynamical equation of the lattice oscillations and their solutions.

23 - What is a phonon dispersion relation

: - Discuss the oscillations of a linear chain of equal atoms

- Discuss the oscillations of a linear chain of two different atoms.

26 - Acoustical and optical modes of oscillation of a lattice.

27 - Measurement of the phonon dispersion relations.

: - The conservation of the crystal momentum: its meaning and the difference with respect to the

conservation of momentum.

- The density of states of the lattice oscillations

30 Specific heats

37 - Quantization of lattice oscillations

- The need of a quantum model for explaining the temperature dependence of the specific heat

32 - The Einstein model of the specific heat

33 - The Debye model of the specific heat

34 Thermal conductivity

- Why the thermal conductivity of a perfect harmonic lattice in infinite

35 - The phenomenological aspects of the temperature dependence of thermal conductivity in solids

36 - How to model thermal conductivity and the role of scattering

37 - Phonon phonon interaction

38 - Normal and umklapp processes and their role in thermal conductivity

39 Bloch theorem

- Approximations in modeling the electron states in a solid

: - Bloch waves: their physical interpretation

- How to demonstrate the Bloch theorem working in the real space

: - How to demonstrate the Bloch theorem working in the reciprocal space

- Periodicity of the electron states in a solid in the reciprocal space

: - The energy bands

- The nearly free electron model

÷ - The tight binding model

- The Fermi surface

48 comparisse

* electron states phonons

-

Electron transport

- The basic ingredients of the semiclassical model of electron transport in solids

49 - The concept of effective mass

50 - Describe the Bloch oscillations and why it is usually impossible to observe them

51 Superconductivity

- The most relevant aspects of superconductivity

52 - The Landau Ginzburg theory of superconductivity

53 - The basic assumptions of the BCS theory of superconductivity

54 implicazioni

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itself

)

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the

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definition

Theme 3 Bravais

of

are

lattice :

PHYSICA

1 L

. (

of points

set such

modes )

called

a has the

then

each

that of sama

firrst

configuration neighbors

of .

MATHEMATICAL

2 .

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of

set

a :

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mia è in )

3D

+

+ space

= ma }

,

,

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c-

mi independent

è nectaris

lineare

i primitive vechoms

called .

SYMMETRY

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translated

as ,

lattice

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the con

define collection of

the

as indipendente transazione

lineare make

that the lattice

aectoms

• itself

overlap .

discount of

a set nonplanarn

with

closed

vertono inesperti

and

operations of

the

to seem .

difference

lahhiees

Amarmi

9 ZD

. possible

In 5

theme Bravais

ZD are

lattica : • •

: •

: !

a •

a &

^ I →

@

> @

@

@ • g

SQUARE RECTANGULAR ED

CENTER

RECTANGULAR

§ • • •

A •

q •

,

a >

→ • •

• ao a

e HEXAGONAL

OBLIQUE structure

Note the is

honeycomb

: NOT lattice

Bravais

a .

10 elementary

Definition basis all

,

. periodici structure

of a .

Seitz cell

Wigner - . objects

collection of phpsical

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( i. Molecular

atoms )

e ,

. itself

rrepeahs at emery

point

lattice . figure

unit cell geometriche

(

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that lattice

all

over

points fills up

completely

space .

Shapes

Note not all

:

tessellate space

can pentagon

( for example :

call

Wigner Seitz :

- lattice

all centene

is

W

a s on

- a

points

point all

the

is in