Quantum Cryptography

Lecture fall 2015

Instructor Dominique Unruh <<surname> at ut dot ee>
Lecture Period September 3, 2015 - December 17, 2015
Lectures Mondays, 14:15-15:45, room 511 (Dominique; may sometimes be switched with tutorial)
Practice sessions
Thursdays, 12:15-13:45, room 512 (Dominique / Ehsan)
Course Material Lecture notes, blackboard photos, practice blackboard photos (zip; huge zip), videos and exam study guide.
Language English
Mailing list ut-qcrypto@googlegroups.com
Exam TBA
Contact Dominique Unruh <<surname> at ut dot ee>

Topics covered

See also the blackboard photos and the practice blackboard photos (zip; huge zip).
2015-09-03 (lecture)Introduction and motivation.
2015-09-07 (lecture)Introduction and motivation (ctd.). Mathematics of single qubits.
2015-09-10 (practice)Short linear algebra recap. Mathematics of polarization filters. (Volunteer: Kristian Kuppart)
2015-09-14 (lecture)Elizur-Veidman bomb tester. Mathematics of multiple qubits.
2015-09-17 (practice)Review of homework 1. Unitary transform. Search for polarization directions invariant under any rotations. (Volunteers: Bahman and Mihkel)
2015-09-21 (lecture)Tensor product. Measurements.
2015-09-24 (practice)Quantum teleportation . (Volunteer: ?)
2015-10-05 (lecture)Measurements in subsystems. Deutsch's algorithm. Toy crypto example.
2015-10-08 (practice)Implementing classical functions as unitaries. (Volunteer: Tore)
2015-10-12 (lecture)Ensembles. Density operators.
2015-10-15 (practice)Toy encryption protocol: security definition and proof. (Volunteer: Yauhen)
2015-10-19 (lecture)Partial trace. Purification.
2015-10-22 (practice)Purification of quantum circuits.
2015-10-26 (practice)Spectral decomposition (Volunteer: Yauhen).
2015-10-29 (lecture)Quantum operations. Statistical distance. Trace distance.
2015-11-02 (lecture)Quantum key distribution (QKD): Idea. Security definition. Bell states. Start of construction/proof.
2015-11-05 (practice)Secure message transfer from QKD: Security definition.
2015-11-09 (lecture)"QKD: Proof continued.
2015-11-12 (practice)Guessing the key in QKD without entanglement purification (started).
2015-11-16 (lecture)"QKD: Proof continued.
2015-11-19 (practice)Guessing the key in QKD without entanglement purification (finished) (Volunteer: Tore).
2015-11-23 (lecture)"QKD: Proof finished .
2015-11-26 (practice)QKD without using bell pairs and quantum memory.
2015-11-30 (lecture)"Commitments (definitions). Impossibility of commitment .
2015-12-03 (practice)Impossibility of oblivious transfer.
2015-12-07 (practice)Simon's algorithm. Attack on the Even-Mansour block cipher (Volunteers: Bahman and Yauhen).
2015-12-10 (lecture)Wave function. Schrödinger equation. Particle in an infinite potential well.
2015-12-14 (lecture)Quantum position-verification: Impossibility classical & quantum. Possibility in BQSM (Proof: started).
2015-12-17 (lecture)Quantum position-verification in BQSM (Proof: finishd).


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
2015-09-082015-09-15Homework 1Solution 1
2015-09-152015-09-22Homework 2Solution 2
2015-09-242015-10-06Homework 3Solution 3
2015-10-072015-10-13Homework 4Solution 4
2015-10-142015-10-20Homework 5Solution 5
2015-10-202015-10-27Homework 6Solution 6
2015-10-302015-11-05Homework 7Solution 7
2015-11-032015-11-10Homework 8Solution 8
2015-11-112015-11-17Homework 9Solution 9
2015-11-182015-11-24Homework 10Solution 10
2015-11-242015-12-01Homework 11Solution 11
2015-12-012015-12-08Homework 12Solution 12
2015-12-122015-12-17Homework 13Solution 13


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.