Quantum @ LIACS

Personal webpage of Vedran Dunjko


Aurora, Trømso




Teaching: Quantum Algorithms



Quantum Algorithms 2020-2021



This year Leiden University shifted to Brightspace, so we will be testing out using this system for the course Quantum Algorithms in the year 2020-2021.
For all information, please go to you Brightspace page of the course.
The materials below may still be convenient for students to get an idea of what the course will cover, and what the assignments will be like; however the course does have new content this year, and certain other improvements.

For any questions regarding the course, send me an email to v.dunjko [at] liacs.leidenuniv.nl with the subject line starting with “QA:”. Otherwise I cannot guarantee a prompt answer.






Quantum Algorithms 2019-2020 (old course materials)

On this webpage you will be able to see all the organizational announcements regarding the course Quantum Algorithms (LIACS), and also you will be able to download relevant teaching materials.

Student confidential data should be accessed via blackboard, accessible from the course web-site.

For any questions regarding the course, send me an email to v.dunjko [at] liacs.leidenuniv.nl with the subject line starting with “QA:”. Otherwise I cannot guarantee a prompt answer.

For consultations, please contact me via email first.
Tutorials are prepared and given by Casper Gyurik.

Updates and uploads

06-01-2020: Due to common demand, the deadline for submitting the mini-projects is now postponed to the 9th January (this Thursday, 23:59 CET). Please, aside from submitting the report, include the file(s) (zip or other archive will do) with the code for the implementations you have developed and used.

18-12-2019: I have sent feedback via email to: Sebastiaan, David, Rintse, Luuk, Max, Marcel, Yannick, Martijn, Joao, Mees, Robin, Dominik, Rachel, Loes, Vince, Orson. If you are not on the list, and should be, let me know. Also, if you did not receive my email, let me know.

18-12-2019: The (very concise) solutions to the take-home assignment 2 are given here (THA2 solutions). Your work has been corrected, and I will be sending you individual feedback during the day. You have all done very well!

3-12-2019: The lecture of Mathys Rennela on quantum backtracking algorithm can be found here (backtracking). The lecture of Charles Moussa on the quantum approximate optimisation algorithm is here (QAOA). The lecture on quantum-kernel-based support vector machines are here (quantum kernel ML). Many many thanks to Mathys and Charles for their excellent contributions to the lectures!

28-11-2019: UPDATE: Projects hot out of the oven: here (mini-project descriptions).

26-11-2019: UPDATE: remark of Problem 5 updated -- the unsung hero strikes again (who shall be given bonus credit for this for THA), and points out the claim I used was buggy and from a buggy paper. When in doubt, go to N&C first. Note, in this problem the objective is not to go into gory details of phase estimation, but to develop the idea how to use it, and what quantities typically control the scaling of algorithms (hence the assumption that the algorithm is guaranteed to always output the best approximation of the phase).

26-11-2019: UPDATE: omission corrected in Problem 5 of THA2: in (c) and (d) we mean the logarithm of 1/\lambda_1 (base 2), or, equivalently, -log of the eigenvalues. Thanks to the unsung hero for spotting this.

25-11-2019: INFORMATION: The lecture today, and until the end of the course, will be taking place in room 412.

22-11-2019: INFORMATION: next Thursday you will be provided mini-project assignments. The idea is to work in groups of 3-4 students, so please arrange the groups by then. It is possible to do a project individually, but group work is likely easier for us and you.

22-11-2019: UPDATE: The second set of take home assignments is available here (THA2). Few more details and remarks have been added relative to the preview I made available on Monday, so use this version. The hand-in deadline is Monday 9th December (more than 14 days). However, as you will be also given projects next week, I advise to do these THA sooner -- this set of exercises is significantly less voluminous compared to THA1.

22-11-2019: The lecture on quantum machine learning (big-data-style) can be found here (QML part 1). I have added a short 3-slide-6-sentence summary of the key ideas at the end of lecture.

22-11-2019: Yesterday we discussed the solutions to the first set of take-home assignments, and students had a chance to appeal and improve their score. In the case you could not make it, and you provided solutions, contact me via email, and I will send you your score, or we can arrange to meet so you can see your evaluation.

18-11-2019: UPDATE: solutions to the take-home assignment 1 are given here (THA1 solutions). Your work has been corrected, and on Thursday (tutorials) you will be given the corrected exercises, and we will discuss the solutions. For most of the students who handed in the first set of exercises, there will be a possibility of improving your score there and then. A sneak preview for the next set of take-home assignments is given here (sneak preview). The assignments may be tweaked a bit, and some extra information may still be provided. In the case there are any questions regarding the second set of assignments, we can discuss this on Thursday. The final assignments will be uploaded this Thursday, and the deadline for handing in will be 2 weeks from that point, on 5th December -- this can be shifted depending on your workload in other courses, we will discuss this on Thursday.



12-11-2019: The python notebook which you will use in the next tutorials can be downloaded here (python notebook).

11-11-2019: ANNOUNCEMENT: for the next tutorials (Thu, Nov 14th) please bing your laptops, it will be a quantum programming session!

11-11-2019: The slides from todays lecture of Casper can be found here (lecture on quantum topological data analysis).

11-11-2019: The slides from the last week tutorials can be downloaded here (tutorial 6, quantum simulation and quantum linear systems). Exercises accompanying these tutorials are available here (exercises 6).

6-11-2019: The lecture notes on Hamiltonian simulation and the quantum system solving algorithm can be found here: (HS & QSL).

4-11-2019: The lecture notes concerting quantum key distribution and the density matrix formalism can be found here: (QKD and DM formalism).

4-11-2019: UPDATE: Comment on your feedback during the consultation hour: regarding Problem 2 (global v.s. relative phase), in the relative phase construction, not all choices of initial state, and measurement basis will be able to detect a relative phase. But *many* will (technically, the input state must have non-zero overlap with the eigenvectors of the unitary relative to which there is a change in relative phase, and a similar condition must hold for the measurement basis). If your choices of initial state and measurement basis do not show sensitivity to the change of relative phase, try using Hadamard-basis input states and Hadamard-basis measurements; the assignment can then also be understood as the task of finding an initial state and a measurement basis which is sensitive to the relative phase (it *always* exists), whereas such a state-basis cannot exist for global phase. However, as this was not specified in the assignment, finding such a choice is not mandatory.


23-10-2019: The first set of take-home assignments can be downloaded here: (take-home assignment 1). Instructions on how to solve them are included. Please provide your solutions in hard-copy, latex preferred, (very) legible handwritten solutions accepted also. The solutions will be collected on the 7th Nov. Penalty for late submissions 1 grade / week. Next Thursday we will be giving a consultation session instead of Tutorials to help you with the assignments.

16-10-2019: Slides from the fifth lecture can be found here (Shor's algorithm).

11-10-2019: The slides from the last two tutorials can be downloaded here (tutorial 4) and here (tutorial 5). Exercises accompanying these tutorials are available here (excercises 4) and here (excercises 5).

1-10-2019: Slides from the fourth lecture can be found here (QFT, QPE, applications). Next lectures will be tutorials working out some of the details of this and the previous lecture.

23-09-2019: Slides from the third lecture can be found here (Grover & applications). If possible, for the next lecture, the interested students are advised to briefly take a look at aspects of upcoming topics, listed on the first slide of the lecture notes. This is not mandatory, but will help you get more out of the lectures.

20-09-2019: ANNOUNCEMENT: next week there will be no tutorials on Thursday 26th Sept. More information will be provided during the lectures next Monday (23rd Sept.).

20-09-2019: The slides from the third tutorial can be downloaded here (tutorial 3). Exercises accompanyign the third tutorial are available here (excercises 3).

16-09-2019: Slides from the second lecture can be found here (repeated part 2 of first lecture with recap) (recap starts on page 23), here (classical and quantum universality), here (CC v.s. QC) and here (Deutsch-Jozsa algorithm).

12-09-2019: The slides from the second tutorial can be downloaded here (tutorial 2). Exercises accompanyign the second tutorial are available here (excercises 2).

09-09-2019: Slides from the first lecture can be found here (part 1) and here (part 2). Pointers to relevant literate are on the first slide of part 1. Next tutorials will still contain quite a bit of linear algebra/complex number reminders and also related exercises, which will be helpful if linear algebra aspects of todays lecture felt fast. If you have any questions regarding the lesson materials, feel free to email me using the subject "QA:...".

09-09-2019: Minor typo in the the background refresher slides (refresher), which was spotted by a keen-eyed student, is now corrected. Thanks!

06-09-2019: The general introduction slides from the first tutorial can be downloaded here (intro). Background refresher slides are available here (refresher), and the first sheet with basic exercises is available here (excercises 1) .

03-09-2019: UPDATE: due to a high enrolment, lectures will have to move as well. The first lecture will take place on Monday 9th September, from 11:15 to 13:00 in SNELLIUS/407-409.

03-09-2019: UPDATE: due to a high enrolment, we had to switch rooms. First tutorial will take place on Thursday, 5th September, from 16:15 to 18:00 in SNELLIUS/B02.