Superconducting Qubits
The Master’s Revision Compendium
Everything to know by heart before the final examination
A self-contained, exam-focused reference: chapter-by-chapter cores, formula sheets,
derivations, scaling laws, concept maps, high-yield lists, and a last-day sheet.
Scope and notation. This compendium reconstructs the standard graduate
superconducting-qubits curriculum (circuit QED), following the conventions of Krantz et al.,
A Quantum Engineer’s Guide to Superconducting Qubits (2019), Kjaergaard et al. (2020),
and Nielsen & Chuang. Natural units ℏ = 1 are used in dynamical equations unless a
formula is explicitly dimensional. It is the companion revision document to the seven-part
Oral Examination Compendium (Mock Orals #1–#7).
Legend: key result [M] = memorize exactly [D] = re-derivable in the exam
,Contents
How to use this compendium 3
1 Superconductivity Essentials and Circuit Quantization 4
2 The Cooper-Pair Box and the Transmon 8
3 Single-Qubit Control and the Rotating Frame 11
4 Circuit QED and Dispersive Readout 14
5 Decoherence: Relaxation, Dephasing, and Sweet Spots 17
6 Noise Spectroscopy and the Filter-Function Formalism 20
7 The Flux Qubit and Fluxonium 23
8 Two-Qubit Gates 26
9 Gate Characterization: Randomized Benchmarking and Tomography 29
10 Quantum Error Correction 32
11 Quantum Algorithms 35
12 Fabrication, Materials, and Two-Level Systems 38
Part 2 — High-Yield Exam Section 42
13 Top 100 Formulas to Know by Heart 42
14 Top 50 Derivations to Reproduce from Memory 46
15 Top 50 Concepts Frequently Tested 48
16 Top 50 Common Mistakes 50
17 Top 50 Physical Interpretations Examiners Expect 52
18 Top 30 Order-of-Magnitude Estimates 54
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,Superconducting Qubits — Master Revision Compendium CONTENTS
19 Top 30 Conceptual Traps 55
Part 3 — The Last-Day Revision Sheet 58
The Last-Day Revision Sheet 58
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, How to use this compendium
The document has three movements, each serving a different stage of revision.
Part 1 — Chapter by chapter. Twelve chapters covering the whole course. Each chapter has
the same six sections: (1) Core Concepts — the ideas, their physical meaning, the assumptions, and
links to other chapters; (2) Essential Formula Sheet — every formula with all symbols defined, va-
lidity conditions, physical meaning, and exam use; (3) Fundamental Derivations — the derivations
to be able to reproduce, with logical steps, critical assumptions, and exam shortcuts; (4) Scaling
Relations and Order-of-Magnitude Estimates; (5) Diagrams and Concept Maps; (6) Typical Exam
Questions. Read these to build and consolidate understanding.
Part 2 — High-yield exam section. Consolidated cross-chapter lists: the Top 100 formulas,
Top 50 derivations, Top 50 concepts, Top 50 mistakes, Top 50 physical interpretations, Top 30
order-of-magnitude estimates, and Top 30 conceptual traps. Use these to self-test and to find your
weak spots.
Part 3 — The last-day revision sheet. A few pages with only the critical formulas, essen-
tial definitions, key diagrams, scaling laws, and results that must be remembered exactly — the
irreducible minimum.
Two tags appear throughout: [M] marks a result to memorize exactly (you will not have time or
footing to derive it), and [D] marks a result you can re-derive under exam conditions if memory
fails. Prioritise the [M] items.
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