Quantum Cryptography

Lecture fall 2017

Instructor Dominique Unruh <<surname> at ut dot ee>
Lecture Period September 4, 2017 - December 19, 2017
Lectures Mondays, 14:15-15:45, room 220 (Dominique; may sometimes be switched with tutorial)
Practice sessions
Tuesdays, 14:15-15:45, room 219 (Dominique / Ehsan)
Course Material Lecture notes, blackboard photos, practice blackboard photos, videos and exam study guide.
Language English
Mailing list ut-qcrypto@googlegroups.com
Exam January 18, 10:00-13:00, Room 111 (Liivi 2)
Contact Dominique Unruh <<surname> at ut dot ee>

Topics covered

See also the blackboard photos and the practice blackboard photos.
2017-09-04 (lecture)Introduction and motivation.[video]
2017-09-11 (lecture)Mathematics of single qubits.[video]
2017-09-12 (practice)Small exercises with single qubits.
2017-09-19 (practice)Elizur-Veidman bomb tester
2017-09-25 (lecture)Mathematics of multiple qubits (except measurements).[video]
2017-09-26 (practice)States invariant under rotation. Simple multi-qubit circuits.
2017-10-02 (lecture)Measurements on multiple qubits. Deutsch's algorithm.[video]
2017-10-03 (practice)Review of homework 1. Quantum teleportation.
2017-10-09 (lecture)Ensembles. Density operators.[video]
2017-10-10 (practice)Review of homework 2. Implementing classical functions using quantum gates.
2017-10-16 (lecture)Operations on density operators.[video]
2017-10-17 (practice)Review of homework 3. Quantum one-time pad.
2017-10-23 (lecture)Partial trace.[video]
2017-10-24 (practice)Purification of quantum circuits. Exercises for computing partial traces.
2017-10-30 (lecture)Quantum operations. Statistical Distance. Trace distance.[video]
2017-10-31 (practice)Review of homework 4. Explicit computation of trace distance. Trace distance of orthogonal states.
2017-11-06 (lecture)Trace distance (ctd). Security definitions for QKD.[video]
2017-11-07 (practice)Analysis of an equivalent QKD security definition.
2017-11-13 (lecture)Construction and security proof of QKD (part 1)[video]
2017-11-14 (practice)Secure message transmission from QKD
2017-11-20 (lecture)Security proof of QKD (part 2)[video]
2017-11-21 (practice)Guessing the key in QKD (if no classical postprocessing used).
2017-11-27 (lecture)Security proof of QKD (part 3, error correction)[video]
2017-11-28 (lecture)Security proof of QKD (part 4, privacy amplification)[video]
2017-12-04 (practice)Review of Homework 7. Proving a missing claim from QKD proof.
2017-12-05 (practice)Proving missing claims from QKD proof.
2017-12-11 (lecture)Commitment: Definitions. Impossibility of information-theoretically secure commitment.[video]
2017-12-12 (practice)Applying the impossibility result to a concrete commitment protocol.
2017-12-18 (lecture)Commitments in the bounded quantum storage model.[video]
2017-12-19 (practice)Question and answer session.


Your current amount of points in the homework can be accessed here (as soon as the first sheet has been corrected).
Out Due Homework Solution
2017-09-112017-09-25Homework 1Solution 1
2017-09-272017-10-04Homework 2Solution 2
2017-10-062017-10-13Homework 3Solution 3
2017-10-162017-10-23Homework 4Solution 4
2017-10-252017-11-01Homework 5Solution 5
2017-11-032017-11-10Homework 6Solution 6
2017-11-142017-11-21Homework 7Solution 7
2017-11-272017-12-08Homework 8Solution 8
2017-12-112017-12-18Homework 9Solution 9
2017-12-302018-01-07Homework 10 


In quantum cryptography we use quantum mechanical effects to construct secure protocols. The paradoxical nature of quantum mechanics allows for constructions that solve problems known to be impossible without quantum mechanics. This lecture gives an introduction into this fascinating area.

Possible topics include:


You need no prior knowledge of quantum mechanics. You should have heard some introductory lecture on cryptography. You should enjoy math and have a sound understanding of linear algebra.


[NC00] Nielsen, Chuang. "Quantum Computation and Quantum Information" Cambridge University Press, 2000. A standard textbook on quantum information and quantum computing. Also contains some quantum cryptography.

Further reading may be suggested during the course. See the "further reading" paragraphs in the lecture notes.