Preface ....................................................... ix
Acknowledgments .............................................. xvi
1 Succinct overview ........................................... 1
Part I Polaron Formation ...................................... 7
2 Electron-phonon interactions ................................ 9
2.1 Long-range electron-phonon interaction ................. 9
2.2 Short-range electron-phonon interactions .............. 11
3 Weak-coupling polarons: carrier-induced softening .......... 13
3.1 Long-range electron-phonon interaction ................ 13
3.2 Short-range electron-phonon interactions .............. 14
3.3 Two-site model: origin of carrier-induced softening ... 15
4 Strong coupling: self-trapping ............................. 21
4.1 Adiabatic formalism ................................... 21
4.2 Self-trapping ......................................... 23
4.3 Scaling approach: large- and small-polaron formation .. 29
4.4 Self-trapping beyond the adiabatic limit .............. 33
4.5 Disorder-assisted small-polaron formation ............. 39
4.6 Synopsis .............................................. 41
5 Dopant- and defect-related small polarons .................. 43
5.1 Small polarons bound to dopants and defects ........... 43
5.2 Small-polaronic impurity conduction ................... 45
6 Molecular polarons ......................................... 49
6.1 General features ...................................... 49
6.2 Examples .............................................. 52
7 Bipolarons ................................................. 54
7.1 Large-bipolaron formation ............................. 55
7.2 Small-bipolarons: negative-U centers .................. 58
7.3 Softening bipolarons .................................. 59
8 Magnetic polarons and colossal magnetoresistance ........... 65
8.1 Magnetic polarons ..................................... 66
8.2 Donor-state collapse in ferromagnets: colossal
magnetoresistance ..................................... 68
Part II Polaron Properties ................................... 73
9 Optical properties ......................................... 75
9.1 Absorption from exciting polarons' self-trapped
carriers .............................................. 75
9.2 Low-frequency absorption from polaron motion .......... 78
9.3 Carriers'photo-generation, recombination and
luminescence .......................................... 81
10 Large-polaron transport .................................... 86
10.1 Coherent versus incoherent transport .................. 86
10.2 Large-polaron effective mass .......................... 88
10.3 Large-polaron scattering .............................. 91
11 Small-polaron transport .................................... 95
11.1 Loss of coherence and hopping transport ............... 95
11.2 Two complementary types of hopping transport .......... 96
11.3 Overview of polaron hopping ........................... 98
11.4 Non-adiabatic polaron jump rate ...................... 102
11.5 Semiclassical treatment of the non-adiabatic
polaron jump rate .................................... 108
11.6 Semiclassical treatment of the adiabatic polaron
jump rate ............................................ 110
11.7 Vibrational relaxation and correlations between
polaron jumps ........................................ 118
11.8 Pair-breaking in semiclassical singlet-bipolaron
hopping .............................................. 121
11.9 Exchange interactions and polaron hopping in
magnetic semiconductors .............................. 123
12 Polarons'Seebeck coefficients ............................. 125
12.1 Definitions and general concepts ..................... 125
12.2 Hopping polarons'Seebeck coefficients ................ 127
12.3 Softening (bi)polarons' Seebeck coefficients ......... 129
12.4 Seebeck coefficients of polarons in magnetic
semiconductors ....................................... 133
13 Polarons' Hall effect ..................................... 135
13.1 Coherent transport's Hall mobility ................... 136
13.2 Microscopic treatment of electric and magnetic
fields ............................................... 138
13.3 Hall mobility for non-adiabatic polaron hopping ...... 140
13.4 Hall mobility for adiabatic polaron hopping .......... 147
13.5 Hall-effect signs for hopping conduction ............. 155
Part III Extending Polaron Concepts ......................... 161
14 Superconductivity of large bipolarons ..................... 163
14.1 Interactions between large bipolarons ................ 164
14.2 Condensation to a large-bipolaronic liquid ........... 165
14.3 Superconductivity and excitations of a large-
bipolaronic liquid ................................... 167
14.4 Distinctive properties of a large-bipolaronic
superconductor ....................................... 168
15 Non-Ohmic hopping conduction and electronic switching ..... 173
15.1 Formalism for steady-state hopping ................... 173
15.2 Low-temperature hopping in a disordered medium ....... 175
15.3 Interfacial small-polaron accretion: a threshold
switching mechanism .................................. 180
16 Electronically stimulated desorption of atoms from
surfaces .................................................. 186
16.1 Model Hamiltonian .................................... 187
16.2 Scaling analysis ..................................... 189
17 Hopping of light atoms .................................... 191
17.1 High-temperature diffusion: excited coincidences
and non-Condon transfers ............................. 191
17.2 Isotope dependences of light-atoms' high-
temperature diffusion constants ...................... 193
17.3 Isotope dependences of light-atoms' low temperature
diffusion constants .................................. 196
References ................................................ 198
Index ........................................................ 209
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