Quantum Paper Club

The Quantum Paper Club is organized by students for students. Its goal is to expose the students interested in Quantum Engineering to the research done in the field. More than this, it is a formidable platform to practice public scientific speaking.

The Quantum Paper Club usually takes place on Thursdays at 17:45 in HIT H42. If you would like to present, please contact Kai Gamlin () or Gaétan Membrez ().

The Quantum Paper Club has concluded for the current semester. We will be back again next semester.

Past Talks

Meeting dateTopicPresenterAbstractLink to reference
26.04.2022 The impact of quantum mechanics on philosophyLev Vaidman (Professor @ Tel Aviv University)
The uncertainty principle and Bell-type correlations led to a dramatic change in the philosophy of science. Today we are ready to accept indeterminism and some kind of action at a distance. I will argue that this move is not necessary and maybe mistaken. Accepting the existence of multiple parallel worlds allows restoring determinism and avoiding action at a distance. The issue of probability in the many-worlds framework, however, requires introducing a novel element in science. Warning: I plan to split the world during the talk!
19.04.2022Dynamic generation of entangled electrons in a Cooper pair splitterFredrik Brange (PostDoc @ Aalto University)
Cooper pair splitters are promising candidates for generating spin-entangled electrons. However, the splitting of Cooper pairs is a random and noisy process, which hinders further synchronized operations on the entangled electrons. To circumvent this problem, we propose and analyze a dynamic Cooper pair splitter that produces a noiseless and regular flow of spin-entangled electrons. The Cooper pair splitter is based on a superconductor coupled to quantum dots, whose energy levels are tuned in and out of resonance to control the splitting process. We identify the optimal operating conditions for which exactly one Cooper pair is split per period of the external drive and the flow of entangled electrons becomes noiseless. To characterize the regularity of the Cooper pair splitter in the time domain, we analyze the g(2) function of the output currents and the distribution of waiting times between split Cooper pairs. Our proposal is feasible using current technology, and it paves the way for dynamic quantum information processing with spin-entangled electrons.
12.04.2022Introduction to dissipation engineeringElias Zapusek (PhD @ ETH TIQI)
Dissipation arises in quantum systems due to interaction with environment. In unitary quantum information processing dissipation is primarily considered as a source of noise. However, we can also use controlled dissipation to manipulate quantum systems. Starting from the most well-known example optical pumping and moving on to more complex schemes I will give a brief introduction to the field of dissipation engineering.
05.04.2022Saving the cat: From open quantum systems to bosonic quantum error correctionDavid Schlegel (PhD @ EPFL)
A popular approach for realizing a fault-tolerant quantum computer is to construct logical qubits encoded in multiple physical two-level qubits. Recent alternative approaches are based on bosonic quantum codes which are quantum error correcting (QEC) codes that redundantly encode quantum information in the states of a quantum harmonic oscillator, making it possible to detect and correct errors, while reducing the hardware resource overhead.
In this talk, I will provide an overview of QEC in bosonic systems and review various bosonic quantum codes such as GKP and cat codes. Furthermore, I will show recent results on a novel bosonic quantum code, called the squeezed cat code, that enables to correct both dephasing and loss errors. We show that with moderate squeezing, and using typical parameters of state-of-the-art quantum hardware platforms, the squeezed cat code has a resilience to loss errors and dephasing errors that significantly outperform that of the conventional cat code.
29.03.2022Hardware-Tailored Diagonalization CircuitsDaniel Miller (PhD @ IBM)
A central building block of many quantum algorithms is the diagonalization of Pauli operators. Although it is always possible to construct a quantum circuit that simultaneously diagonalizes a given set of commuting Pauli operators, only resource-efficient circuits are reliably executable on near-term quantum computers. Generic diagonalization circuits can lead to an unaffordable Swap-gate overhead on quantum devices with limited hardware connectivity. A common alternative is excluding two-qubit gates, however, this comes at the cost of restricting the class of diagonalizable sets of Pauli operators to tensor product bases (TPBs). In this letter, we introduce a theoretical framework for constructing hardware-tailored (HT) diagonalization circuits. We apply our framework to group the Pauli operators occurring in the decomposition of a given Hamiltonian into jointly-HT-diagonalizable sets. We investigate several classes of popular Hamiltonians and observe that our approach requires a smaller number of measurements than conventional TPB approaches. Finally, we experimentally demonstrate the practical applicability of our technique, which showcases the great potential of our circuits for near-term quantum computing.
22.03.2022Photon-Pair generation from single LiNbO3 microcubes and GaAs nanowiresSaerens Grégoire (PhD @ ETH)
Nonclassical light sources are highly sought after as they are an integral part of quantum communication
and quantum computation devices. Typical sources rely on bulk crystals that are not compact and have limited bandwidth due to phase-matching conditions.
Here I will present generation of photon pairs at the telecommunication wavelength from free-standing LiNbO 3 microcubes and free-standing GaAs cut Nanowires using the spontaneous parametric down- conversion process. I will show the fabrication process for each of this nanostructure, the setup configuration for free space spontaneous parametric down-conversion, as well as the alignment challenges when trying to observe this wavelength conversion process in transmission. We will compare experimental as well as simulation results for both nanostructures.
15.03.2022No session – Pauli Lectures
08.03.2022Quantum Memories in a Quantum NetworkMoritz Businger (PhD @ UNIGE)

Quantum memories are one of the corner stones in a quantum network. It enables communication beyond the loss limit of direct communication and lets us use more complex protocols for quantum computation. Here I will present the ensemble based quantum memory approach we are perusing in Geneva and show how this lets us store a record number of quantum states in a rare earth ion doped crystal. Especially our recent work on Ytterbium is very competitive in terms of capacity and storage time which makes it a perfect candidate implementation in a largescale quantum network.
01.03.2022Blueprint for a Scalable Photonic Fault-Tolerant Quantum Computer Ilan Tzitrin and Eli Bourassa (Xanadu)Link
14.12.2021Realizing Repeated Quantum Error Correction in a Distance-Three Surface CodeNathan Lacroix (PhD @ Qudev, ETH)Link
07.11.2021Joint measurability of binary qubit measurementsDmitry Grinko (PhD @ U. o. Amsterdam)
30.11.2021An addressable quantum dot qubit with
fault-tolerant control-fidelity
Markus NieseLink
23.11.2021Universal quantum computation with ideal Clifford gates and noisy ancillas
Ivan Rojkov (PhD @ TIQI, ETH)Link
16.11.2021Frequency-domain Hong-Ou-Mandel interferenceDario ScheiwillerLink
09.11.2021Strong Optomechanical Coupling at Room TemperatureDr. Nadine Meyer (Senior Scientist @ NSL, ETH)
02.11.2021Measurement of Subpicosecond Time Intervals between Two Photons by InterferenceMoritz Fontboté SchmidtLink
26.10.2021Test of the Local Realism and Realism in Particle PhysicsAnna EfimovaLink
21.10.2021Stabilization and operation of a Kerr-cat qubit in a nonlinear superconducting resonatorDr. Alexander Grimm (PSI)Link
14.10.2021Error correction with real-time Feedback for Surface 17 on the Zurich Instruments setupLiberto Beltrán

Demonstrating the power of state-of-the-art quantum computersElisa Bäumer (PhD @ Renner/ETH+IBM)

Bulk crystalline optomechanicsElisa Bäumer (PhD @ Renner/ETH+IBM)Link

Constructing quantum codes from any classical code and their embedding in ground space of local HamiltoniansDina Abdelhadi, (PhD @ EPFL)Link

Controlling the competition between coherent and dissipative processes in a superradiant quantum gas.Francesco Ferri (Postdoc @ Esslinger/ETH)Link

Strawberry Fields: A Software Platform for Photonic Quantum ComputingIvan Rojkov/Moritz Fontboté SchmidtLink
03.06.2021A gate-tunable, field-compatible fluxoniumMarta Pita Vidal (TU Delft)Link
27.05.2021Qiskit Pulse: Programming Quantum Computers Through the Cloud with PulsesCaroline TornowLink
20.05.2021Quantum Architecture Search via Deep Reinforcement LearningKristina KirovaLink
13.05.2021Generation of Nonclassical Motional States of a Trapped AtomMoritz Fontboté SchmidtLink
06.05.2021Quantum acoustics with superconducting qubitsAlessandro Bruno Link
29.04.2021Chiral Quantum OpticsChaoxin DingLink
15.04.2021Quantum error correction of a qubit encoded in grid states of an oscillatorAlec Eickbusch (PhD student at Prof. Devoret’s Qulab at Yale University)Link
01.04.2021A four-qubit germanium quantum processorIvan RojkovLink
25.03.2021Predicting many properties of a quantum system
from very few measurements
Ivan RojkovLink
18.03.2021A network-ready random-access qubits memoryStefano MartiLink
11.03.2021How to put quantum particles on magic bullet trajectories that can hit two targets without a clear line-of-sightIvan RojkovLink
02.03.2021SpinQ Gemini: a desktop quantum computer for education and researchMoritz Fontboté SchmidtLink
23.02.2021Strongly correlated Fermions strongly coupled to lightProf. Jean-Philippe Brantut (EPFL)Laboratory for Quantum Gases
08.12.2020Error correction of a logical grid state qubit by dissipative pumpingIvan Rojkov &
Moritz Fontboté Schmidt
1.12.2020Observation of coherent optical information storage in anatomic medium using halted light pulsesMoritz Fontboté SchmidtLink
24.11.2020Quantum memories for photonsDr. Mikael AfzeliusQuantum Repeaters & Memories
17.11.2020Measurement of subpicosecond time intervals between two photons by interferenceMoritz Fontboté Schmidt Link
10.11.2020Quantum-dot spin–photon entanglement via frequency downconversion to telecom wavelengthMarco StuckiLink
03.11.2020Observation of entanglement between a quantum dot spin and a single photonChaoxin DingLink
27.10.2020An introduction to Pound–Drever–Hall laser frequency stabilization Moritz Fontbote Schmidt &
Benjamin van Ommen
20.10.2020Cavity Quantum Electrodynamics at Arbitrary Light-Matter Coupling StrengthsAlperen TügenLink
13.10.2020Architecture for a large-scale ion-trapquantum computerIvan RojkovLink
06.10.2020Interaction-assisted reversal of thermopower with ultracold atoms Moritz Fontbote SchmidtLink
29.09.2020Charge Insensitive Qubit Design derived from the Cooper Pair BoxMoritz Fontbote Schmidt Link
22.09.2020Hartree-Fock on a superconducting qubit quantum computerIvan RojkovLink
21.07.2020Generation of entangled photon states in optical down-conversion and up-conversion processes.Sahnawaz Alam (MSc in Physics at Indian Institute of Technology Gandhinagar)
07.07.2020From nanotech to living sensors:unraveling the spin physics of biosensing at the nanoscaleProf. Clarice D. Aiello (Assistant professor at UCLA and head of the Quantum Biology Tech (QuBiT) Lab )
30.06.2020Direct Measurement of the Density Matrix of a Quantum SystemAlperen TügenPaper
23.06.2020Proof-of-concept proposal for machine learning using superconducting qubits (Master Thesis)Colin ScaratoContact speaker
16.06.2020Normal-Mode Splitting in a Weakly Coupled Optomechanical System Francesco AdinolfiPaper
09.06.2020Optimal cooling of a spin-boson systemEmanuel Malvetti (Semester thesis)Contact speaker
02.06.2020Direct measurement of the Zak phase in topological Bloch bandsBenjamin van OmmenPaper
26.05.2020Ramsey interferometry with dissipative quantum error correctionIvan Rojkov (Semester thesis)Contact speaker
19.05.2020Cavity-Based 3D Cooling of a Levitated Nanoparticle via Coherent ScatteringDominik Windey (Phd Student in the Novotny/Photonics group)Paper, PDF of presentation
12.05.2020Integrated optical multi-ion quantum logicChi Zhang (PhD student in the Home/TIQIgroup)Paper
05.05.2020Topological Quantum ComputingOriel KissLecture notes by Preskill
28.04.2020Remote quantum entanglement between two micromechanical oscillatorsMarco StuckiPaper
21.04.2020Non-classical correlations between single photons and phonons from a mechanical oscillatorChaoxin DingPaper
15.04.2020Reinforcement Learning in Different Phases of Quantum ControlPedro RossoPaper
08.04.2020Cavity-Assisted Quantum Bath EngineeringMoritz Fontboté SchmidtPaper
1.04.2020Error-mitigated quantum gates exceeding physical fidelities in a trapped-ion systemMoritz Fontboté SchmidtPaper
10.03.2020To catch and reverse a quantum jump mid flightAlperen TugenPaper
02.03.2020Entanglement of two quantum memories via fibres over dozens of kilometresMoritz Fontboté SchmidtPaper
25.02.2020Atom-by-atom assembly of defect-free one-dimensional cold atom arraysYongxin SongPaper
18.02.2020Fast two-qubit logic with holes in GermaniumMoritz Fontboté SchmidtPaper
17.12.19How often should you beat your kids?Moritz Fontboté SchmidtPaper
10.12.2019Single-Shot Quantum Nondemolition Detection of Individual Itinerant Microwave PhotonsMoritz Fontboté SchmidtPaper
03.12.2019Universal Gate for Fixed-Frequency Qubits via a Tunable BusMoritz Fontboté SchmidtPaper
26.11.2019Ultracold and unreactive fermionic molucules and A degenerate Fermi gas of polar MoleculesMarit FiechterPaper and Paper
19.11.2019Measurement of subpicosecond time intervals between two photons by interferenceMoritz Fontboté SchmidtPaper
12.11.2019Towards fault-tolerant quantum computing with trapped ionsMoritz Fontboté SchmidtPaper
05.11.2019Quantum Computations with Cold Trapped IonsMoritz Fontboté SchmidtPaper
29.10.2019Nanoscale imaging magnetometry with diamond spins under ambient conditionsAlperen Tügen, Moritz Fontboté SchmidtPaper
22.10.2019Charge Insensitive qubit design derived from the cooper pair boxBenjamin Van Ommen, Alperen Tugen, Moritz Fontboté SchmidtPaper

If not noted otherwise, presenters were ETH students.