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Metals: the Drude and Sommerfeld models |
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1 | (15) |
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1 | (1) |
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What do we know about metals? |
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1 | (1) |
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2 | (2) |
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2 | (1) |
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The relaxation-time approximation |
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3 | (1) |
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The failure of the Drude model |
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4 | (3) |
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4 | (1) |
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Thermal conductivity and the Wiedemann-Franz ratio |
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4 | (2) |
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6 | (1) |
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7 | (1) |
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7 | (6) |
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The introduction of quantum mechanics |
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7 | (2) |
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The Fermi-Dirac distribution function |
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9 | (1) |
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The electronic density of states |
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9 | (1) |
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The electronic density of states at E ≈ EF |
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10 | (1) |
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The electronic heat capacity |
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11 | (2) |
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Successes and failures of the Sommerfeld model |
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13 | (3) |
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The quantum mechanics of particles in a periodic potential: Bloch's theorem |
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16 | (7) |
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Introduction and health warning |
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16 | (1) |
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Introducing the periodic potential |
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16 | (1) |
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Born-von Karman boundary conditions |
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17 | (1) |
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The Schrodinger equation in a periodic potential |
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18 | (1) |
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19 | (1) |
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20 | (3) |
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The nearly-free electron model |
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23 | (9) |
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23 | (1) |
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23 | (3) |
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Single electron energy state |
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23 | (1) |
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Several degenerate energy levels |
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24 | (1) |
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Two degenerate free-electron levels |
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24 | (2) |
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Consequences of the nearly-free-electron model |
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26 | (6) |
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27 | (1) |
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Elements with even numbers of valence electrons |
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27 | (2) |
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More complex Fermi surface shapes |
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29 | (3) |
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32 | (9) |
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32 | (1) |
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Band arising from a single electronic level |
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32 | (3) |
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32 | (1) |
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33 | (1) |
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The potential and Hamiltonian |
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33 | (2) |
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General points about the formation of tight-binding bands |
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35 | (6) |
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The group IA and IIA metals; the tight-binding model viewpoint |
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36 | (1) |
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36 | (1) |
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37 | (4) |
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Some general points about bandstructure |
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41 | (8) |
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Comparison of tight-binding and nearly-free-electron bandstructure |
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41 | (1) |
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42 | (3) |
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42 | (1) |
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42 | (1) |
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42 | (1) |
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The effective mass and the density of states |
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43 | (1) |
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Summary of the properties of k |
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44 | (1) |
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Scattering in the Block approach |
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45 | (1) |
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45 | (1) |
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46 | (3) |
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Semiconductors and Insulators |
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49 | (16) |
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49 | (1) |
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Bandstructure of Si and Ge |
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50 | (3) |
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50 | (1) |
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51 | (1) |
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51 | (1) |
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Constant energy surfaces in the conduction bands of Si and Ge |
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52 | (1) |
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Bandstructure of the direct-gap III-V and II-VI semiconductors |
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53 | (3) |
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53 | (1) |
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53 | (1) |
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Optical absorption and excitons |
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54 | (1) |
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55 | (1) |
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Constant energy surfaces in direct-gap III-V semiconductors |
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56 | (1) |
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Thermal population of bands in semiconductors |
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56 | (9) |
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56 | (2) |
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The motion of the chemical potential |
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58 | (1) |
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Intrinsic carrier density |
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58 | (1) |
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Impurities and extrinsic carriers |
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59 | (1) |
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Extrinsic carrier density |
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60 | (2) |
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Degenerate semiconductors |
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62 | (1) |
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62 | (1) |
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Is it a semiconductor or an insulator? |
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62 | (1) |
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A note on photoconductivity |
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63 | (2) |
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Bandstructure engineering |
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65 | (20) |
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65 | (1) |
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65 | (1) |
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66 | (9) |
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Growth of semiconductor multilayers |
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66 | (2) |
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Substrate and buffer layer |
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68 | (1) |
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68 | (1) |
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Optical properties of quantum wells |
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69 | (1) |
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Use of quantum wells in opto-electronics |
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70 | (1) |
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71 | (1) |
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Type I and type II superlattices |
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71 | (2) |
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Heterojunctions and modulation doping |
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73 | (1) |
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The envelope-function approximation |
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74 | (1) |
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Band engineering using organic molecules |
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75 | (3) |
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75 | (1) |
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Molecular building blocks |
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75 | (2) |
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77 | (1) |
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A note on the effective dimensionality of Fermi-surface sections |
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78 | (1) |
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Layered conducting oxides |
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78 | (3) |
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81 | (4) |
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Measurement of bandstructure |
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85 | (32) |
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85 | (1) |
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85 | (2) |
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85 | (1) |
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85 | (2) |
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Orbits on a Fermi surface |
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87 | (1) |
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The introduction of quantum mechanics |
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87 | (4) |
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87 | (2) |
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Application of Bohr's correspondence principle to arbitrarily-shaped Fermi surfaces in a magnetic field |
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89 | (1) |
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Quantisation of the orbit area |
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90 | (1) |
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The electronic density of states in a magnetic field |
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91 | (1) |
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Quantum oscillatory phenomena |
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91 | (6) |
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Types of quantum oscillation |
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93 | (1) |
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The de Haas-van Alphen effect |
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94 | (2) |
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Other parameters which can be deduced from quantum oscillations |
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96 | (1) |
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97 | (1) |
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97 | (3) |
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Cyclotron resonance in metals |
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98 | (1) |
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Cyclotron resonance in semiconductors |
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98 | (2) |
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Interband magneto-optics in semiconductors |
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100 | (2) |
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102 | (3) |
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Angle-resolved photoelectron spectroscopy (ARPES) |
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103 | (1) |
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Electroreflectance spectroscopy |
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104 | (1) |
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105 | (7) |
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105 | (1) |
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Recent controversy: Sr2RuO4 |
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106 | (1) |
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Studies of the Fermi surface of an organic molecular metal |
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106 | (6) |
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Quasiparticles: interactions between electrons |
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112 | (5) |
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Transport of heat and electricity in metals and semiconductors |
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117 | (16) |
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A brief digression; life without scattering would be difficult! |
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117 | (2) |
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Thermal and electrical conductivity of metals |
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119 | (8) |
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Metals: the `Kinetic theory' of electron transport |
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119 | (1) |
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What do τ&sigma and τκ represent? |
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120 | (2) |
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122 | (1) |
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Emission and absorption of phonons |
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122 | (1) |
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What is the characteristic energy of the phonons involved? |
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123 | (1) |
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Electron-phonon scattering at room temperature |
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123 | (1) |
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Electron-phonon scattering at T ≪ θD |
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123 | (1) |
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Departures from the low temperature σα T-5 dependence |
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124 | (1) |
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Very low temperatures and/or very dirty metals |
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124 | (1) |
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125 | (1) |
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Electron-electron scattering |
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125 | (2) |
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Electrical conductivity of semiconductors |
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127 | (2) |
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Temperature dependence of the carrier densities |
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127 | (1) |
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The temperature dependence of the mobility |
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128 | (1) |
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Disordered systems and hopping conduction |
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129 | (4) |
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Thermally-activated hopping |
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129 | (1) |
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130 | (3) |
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Magnetoresistance in three-dimensional systems |
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133 | (10) |
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133 | (1) |
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Hall effect with more than one type of carrier |
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133 | (2) |
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133 | (2) |
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Hall effect in the presence of electrons and holes |
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135 | (1) |
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A clue about the origins of magnetoresistance |
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135 | (1) |
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Magnetoresistance in metals |
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135 | (4) |
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The absence of magnetoresistance in the Sommerfeld model of metals |
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135 | (2) |
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The presence of magnetoresistance in real metals |
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137 | (1) |
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The use of magnetoresistance in finding the Fermi-surface shape |
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138 | (1) |
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139 | (4) |
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Magnetoresistance in two-dimensional systems and the quantum Hall effect |
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143 | (11) |
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Introduction: two-dimensional systems |
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143 | (1) |
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Two-dimensional Landau-level density of states |
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144 | (3) |
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Resistivity and conductivity tensors for a two-dimensional system |
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145 | (2) |
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Quantisation of the Hall resistivity |
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147 | (2) |
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Localised and extended states |
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148 | (1) |
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A further refinement- spin splitting |
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148 | (1) |
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149 | (1) |
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The fractional quantum Hall effect |
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150 | (1) |
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More than one subband populated |
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151 | (3) |
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Inhomogeneous and hot carrier distributions in semiconductors |
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154 | (11) |
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Introduction: inhomogeneous carrier distributions |
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154 | (2) |
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The excitation of minority carriers |
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154 | (1) |
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155 | (1) |
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Diffusion and recombination |
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155 | (1) |
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Drift, diffusion and the Einstein equations |
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156 | (2) |
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Characterisation of minority carriers; the Shockley-Haynes experiment |
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156 | (2) |
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Hot carrier effects and ballistic transport |
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158 | (7) |
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Drift velocity saturation and the Gunn effect |
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158 | (2) |
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160 | (1) |
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A simple resonant tunnelling structure |
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160 | (1) |
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Ballistic transport and the quantum point contact |
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161 | (4) |
A Useful terminology in condensed matter physics |
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165 | (7) |
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165 | (1) |
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165 | (1) |
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165 | (1) |
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165 | (1) |
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Physical properties of crystals |
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166 | (1) |
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166 | (1) |
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167 | (1) |
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Designation of directions |
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167 | (1) |
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Designation of planes; Miller indices |
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168 | (1) |
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Conventional or primitive? |
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169 | (2) |
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171 | (1) |
B Derivation of density of states in k-space |
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172 | (3) |
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172 | (3) |
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173 | (1) |
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174 | (1) |
C Derivation of distribution functions |
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175 | (6) |
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175 | (6) |
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178 | (1) |
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178 | (1) |
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The Maxwell-Boltzmann distribution function |
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178 | (1) |
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Mean energy and heat capacity of the classical gas |
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179 | (2) |
D Phonons |
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181 | (10) |
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181 | (1) |
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182 | (3) |
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Extension to three dimensions |
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183 | (2) |
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185 | (6) |
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187 | (1) |
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Summary; the Debye temperature as a useful energy scale in solids |
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188 | (1) |
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A note on the effect of dimensionality |
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188 | (3) |
E The Bohr model of hydrogen |
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191 | (3) |
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191 | (1) |
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192 | (1) |
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192 | (2) |
F Experimental considerations in measuring resistivity and Hall effect |
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194 | (6) |
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194 | (1) |
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194 | (2) |
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196 | (1) |
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197 | (1) |
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Mobility spectrum analysis |
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198 | (1) |
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The resistivity of layered samples |
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198 | (2) |
G Canonical momentum |
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200 | (1) |
H Superconductivity |
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201 | (4) |
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201 | (1) |
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201 | (2) |
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Pairing and the Meissner effect |
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203 | (2) |
I List of selected symbols |
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205 | (4) |
J Solutions and additional hints for selected exercises |
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209 | (8) |
Index |
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217 | |